<PAGE>

    AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON NOVEMBER 27, 2002

                                                   REGISTRATION NO. 333-________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                       -----------------------------------
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
                       -----------------------------------
                                MERCK & CO., INC.
             (Exact Name of Registrant as Specified in Its Charter)
                                  P.O. BOX 100
                                 ONE MERCK DRIVE
                      WHITEHOUSE STATION, NEW JERSEY 08889
                    (Address of Principal Executive Offices)

       NEW JERSEY                                    22-1109110
(State of Incorporation)                 (I.R.S. Employer Identification Number)


                       MERCK & CO., INC. DEFERRAL PROGRAM
                            (Full Title of the Plan)

                             CELIA A. COLBERT, ESQ.
             VICE PRESIDENT, SECRETARY AND ASSISTANT GENERAL COUNSEL
                                MERCK & CO., INC.
                                  P.O. BOX 100
                                 ONE MERCK DRIVE
                      WHITEHOUSE STATION, NEW JERSEY 08889
                                 (908) 423-1000
            (Name, Address and Telephone Number of Agent for Service)



                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
                                                               PROPOSED MAXIMUM    PROPOSED MAXIMUM
         TITLE OF SECURITIES               AMOUNT TO BE         OFFERING PRICE         AGGREGATE          AMOUNT OF
          TO BE REGISTERED                  REGISTERED            PER SHARE       OFFERING PRICE (3)  REGISTRATION FEE

<S>                                    <C>                     <C>                <C>                 <C>
Deferred Compensation Obligations (1)      $200,000,000              100%           $200,000,000           $18,400

Common Stock, par value $.01 per
 share (2)                             1,000,000 shares (4)        $58.80           $ 58,800,000           $ 5,410
</TABLE>


(1)   The Deferred Compensation Obligations are unsecured obligations of Merck &
      Co., Inc. to pay deferred compensation in accordance with the terms of the
      Merck & Co., Inc. Deferral Program.
<PAGE>
(2)   Includes an indeterminate number of shares of Common Stock that may be
      issuable by reason of stock splits, stock dividends or similar
      transactions in accordance with Rule 416 under the Securities Act of 1933.

(3)   The prices stated above are estimated solely for the purpose of
      determining the registration fee and is based on the average of the high
      and low market prices of the stock as reported on the New York Stock
      Exchange listed issues on November 21, 2002.

(4)   Estimated maximum number of shares of Common Stock of Merck & Co., Inc.
      issuable during the next five years of operation of the Merck & Co., Inc.
      Deferral Program.


                                       2
<PAGE>
                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE

      The following documents and any future filings made with the Securities
and Exchange Commission (Exchange Act File No. 1-3305) are incorporated herein
by reference:

      (a)   Current Report on Form 8-K filed on January 30, 2002;

      (b)   Current Report on Form 8-K filed on March 5, 2002 (amended by a
            Form 8-K/A filed on March 21, 2002);

      (c)   Annual Report on Form 10-K filed on March 21, 2002, for the fiscal
            year ended December 31, 2001;

      (d)   Proxy Statement filed on March 21, 2002, for the Annual Meeting of
            Stockholders held on April 23, 2002;

      (e)   Quarterly Report on Form 10-Q filed on May 13, 2002, for the quarter
            ended March 31, 2002;

      (f)   Form 11-K Annual Report filed on June 27, 2002, for the fiscal year
            ended December 31, 2001;

      (g)   Quarterly Report on Form 10-Q filed on August 13, 2002, for the
            quarter ended June 30, 2002;

      (h)   Quarterly Report on Form 10-Q filed on November 13, 2002, for the
            quarter ended September 30, 2002;

      (i)   The descriptions of the Common Stock of the registrant set forth in
            the registrant's Registration Statements pursuant to Section 12 of
            the Securities Exchange Act of 1934 (the "Exchange Act"), and any
            amendment or report filed for the purpose of updating such
            description.

      The Company's consolidated financial statements for each of the years
ended 2001, 2000 and 1999, included in the Company's Form 10-K and incorporated
by reference herein, have been audited by Arthur Andersen LLP ("Arthur
Andersen"). On February 26, 2002, the Company dismissed Arthur Andersen as its
independent public accountants and engaged PricewaterhouseCoopers LLP to serve
as the Company's independent public accountants for the fiscal year 2002. The
Company understands that the staff of the Securities and Exchange Commission
has taken the position that it will not accept consents from Arthur Andersen if
the engagement partner and the manager for the Company's audit are no longer
with Arthur Andersen. Both the engagement partner and the manager for the
Company's audit are no longer with Arthur Andersen and Arthur Andersen has
ceased practicing before the Securities and Exchange Commission. As a result,
the Company has been unable to obtain Arthur Andersen's written consent to the
incorporation by reference into this registration statement of their audit
report with respect to the Company's financial statements. Under these
circumstances, Rule 437a under the Securities Act of 1933 (the "Securities
Act") permits the Company to file this registration statement without a written
consent from Arthur Andersen. Because Arthur Andersen has not consented to the
inclusion of their report in this registration statement, Arthur Andersen will
not have any liability under Section 11(a) of the Securities Act for any untrue
statements of a material fact contained in the financial statements audited by
Arthur Andersen and incorporated by reference herein or any omission of a
material fact required to be stated therein. Accordingly, investors will not be
able to assert a claim against Arthur Andersen under Section 11(a) of the
Securities Act for any purchases of securities under this registration
statement.



ITEM 4. DESCRIPTION OF SECURITIES

      The obligations of the Company registered hereunder (the "Obligations")
are unsecured general obligations of the Company to pay the value of deferred
compensation accounts in accordance with the terms and conditions of the Merck &
Co., Inc. Deferral Program (the "Program"). The following discussion of the
Program is not a complete description of the Program and is qualified in its
entirety by the full text of the Program. The filing of this Registration
Statement on Form S-8 is not, and should not be construed as, an admission that
the Obligations constitute securities as defined by any applicable federal,
state or local law, or that registration of the Obligations is required under
any such law.

      The Program is a nonqualified deferred compensation plan for eligible
members of management (the "Participants") of the Company and its subsidiaries
and affiliates. Under the Program, the Company will provide all Participants
with the opportunity to defer income earned under various incentive plans of the
Company and certain Participants with the opportunity to defer base salary.


                                       3
<PAGE>
      The Compensation and Benefits Committee of the Board of Directors of the
Company is the administrator of the Program. Unless delegated to another party,
the administrator of the Program is responsible for determining and periodically
reviewing the investment alternatives available under the Program.

      Amounts deferred pursuant to the Program are credited to a deferred
compensation account maintained on behalf of each Participant. A Participant may
initially allocate the amounts credited to his or her deferral account among
various investment alternatives including the Company's common stock and
numerous mutual funds (as determined by the administrator). The Obligations are
adjusted to reflect the performance, whether positive or negative, of the
selected investment alternatives during the deferral period, in accordance with
the terms of the Program. Participants bear the risk that the value of the
Company's common stock, as well as that of all other investment alternatives
available under the Program, will decrease during the deferral period. The
Obligations are general unsecured and unsubordinated obligations of the Company
from time to time outstanding.

      Based on the amount of money allocated to each investment alternative,
Participants are credited with the number of full and partial shares of Company
stock or other fund that the deferred amount allocated to each alternative would
purchase based on the closing price of Company stock or the closing net asset
value of the mutual fund, respectively, on the date that the money would
otherwise have been paid as base salary or incentive compensation. Company
shares and mutual fund shares are not purchased or earmarked for a Participant's
account. A Participant's right to the Obligations cannot be transferred,
assigned, pledged or encumbered except by a written designation of a beneficiary
under the terms of the Program. There is no trading market for the Obligations.

      Participants may redesignate amounts credited to their deferred
compensation accounts among the available investment options in 1% increments at
any time. Notwithstanding the foregoing, Participants are generally not
permitted to redesignate deferred amounts (i) into common stock of the Company
or (ii) out of common stock of the Company other than amounts held in Company
stock in excess of three times base salary.

      As a general rule, at the time of the election to defer compensation, each
Participant elects (i) the time at which distribution of his or her account
balance will occur and (ii) whether such distribution will be in the form of a
lump sum payment or any number of annual installments up to a maximum of 15.
Distributions of amounts allocated to mutual funds and partial shares of Company
stock will be made in cash and distribution of amounts allocated to full shares
of Company stock will generally be made in shares of Company stock.

      The Obligations are not convertible into securities of the Company, except
that Obligations denominated as full shares of Company stock are payable as
shares of Company common stock upon distribution. The Obligations will not have
the benefit of a negative pledge or any other affirmative or negative covenant
on the part of the Company. No trustee has been appointed having the authority
to take action with respect to the Obligations, and each Participant will be
responsible for acting independently with respect to, among other things, the
giving of notices, responding to any requests for consents, waivers, or
amendments pertaining to the Obligations, enforcing covenants and taking action
upon a default.

      The Company has reserved the right to amend the Program at any time,
except that no such amendment shall adversely affect the right of each
Participant to the amounts credited to his or her deferred compensation account
as of the date of the amendment.


                                       4
<PAGE>
ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL

      The legality of the securities offered pursuant to this Registration
Statement will be passed upon for the Company by Celia A. Colbert, Esq., Vice
President, Secretary and Assistant General Counsel of the Company.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS

      The New Jersey Business Corporation Act provides that a New Jersey
corporation has the power to indemnify a director or officer against his or her
expenses and liabilities in connection with any proceeding involving the
director or officer by reason of his or her being or having been such a director
or officer, other than a proceeding by or in the right of the corporation, if
such a director or officer acted in good faith and in a manner he or she
reasonably believed to be in or not opposed to the best interests of the
corporation; and with respect to any criminal proceeding, such director or
officer had no reasonable cause to believe his or her conduct was unlawful.

      The indemnification and advancement of expenses shall not exclude any
other rights, including the right to be indemnified against liabilities and
expenses incurred in proceedings by or in the right of the corporation, to which
a director or officer may be entitled under a certificate of incorporation,
bylaw, agreement, vote of stockholders, or otherwise; provided that no
indemnification shall be made to or on behalf of a director or officer if a
judgment or other final adjudication adverse to the director or officer
establishes that his or her acts or omissions (a) were in breach of his or her
duty of loyalty to the corporation or its stockholders, (b) were not in good
faith or involved a knowing violation of law or (c) resulted in receipt by the
director or officer of an improper personal benefit.

      The Company's Restated Certificate of Incorporation provides that, to the
fullest extent permitted by the laws of the State of New Jersey, directors and
officers of the Corporation shall not be personally liable to the Corporation or
its stockholders for damages for breach of any duty owed to the Corporation or
its stockholders, except that a director or officer shall not be relieved from
liability for any breach of duty based upon an act or omission (a) in breach of
such person's duty of loyalty to the Corporation or its stockholders, (b) not in
good faith or involving a knowing violation of law or (c) resulting in receipt
by such person of an improper personal benefit.

      The By-Laws of the Company provide that a former, present or future
director, officer or employee of the Company or the legal representative of any
such director, officer or employee shall be indemnified by the Company: (a)
against reasonable costs, disbursements and counsel fees paid or incurred where
such person has been successful in the defense on the merits or otherwise of any
pending, threatened or completed civil, criminal, administrative or arbitrative
action, suit or proceeding, and any appeal therein and any inquiry or
investigation which could lead to such action, suit, or proceeding, or in the
defense of any claim, issue, or matter therein, brought by reason of such
person's being or having been such director, officer or employee, and (b) with
respect to the defense of any such action, suit, proceeding, inquiry or
investigation for which indemnification is not made under (a) above, against
reasonable costs, disbursements (which shall include amounts paid in
satisfaction of settlements, judgments, fines and penalties, exclusive, however,
of any amount paid or payable to the Company) and counsel fees if such person
acted in good faith and in a manner such person reasonably believed to be in or
not opposed to the best interests of the Company, and in connection with any
criminal proceedings such person also had no reasonable cause to believe the
conduct was unlawful, with the determination as to whether the applicable
standard of conduct was met to be made by a majority of the members of the Board
of Directors (sitting as a Committee of the Board) who were not parties to such
inquiry, investigation, action, suit or proceeding or by any one or more
disinterested counsel to whom the


                                       5
<PAGE>
question may be referred by the Board of Directors; provided, however, in
connection with any proceeding by or in the right of the Company, no
indemnification shall be provided as to any person adjudged by any court to be
liable to the Company except as and to the extent determined by such court.

      The Company enters into indemnification agreements with its directors and
officers and enters into insurance agreements on its own behalf. The
indemnification agreements provide that the Company agrees to hold harmless and
indemnify its directors and officers to the fullest extent authorized or
permitted by the Business Corporation Act of the State of New Jersey, or any
other applicable law, or by any amendment thereof or other statutory provisions
authorizing or permitting such indemnification that is adopted after the date
hereof. Without limiting the generality of the foregoing, the Company agrees to
hold harmless and indemnify its directors and officers to the fullest extent
permitted by applicable law against any and all expenses, judgments, fines, and
amounts paid in settlement actually and reasonably incurred by its directors and
officers in connection with the defense of any present or future threatened,
pending, or completed claim, action, suit, or proceeding by reason of the fact
that they were, are, shall be, or shall have been a director or officer of the
Company, or are or were serving, shall serve, or shall have served, at the
request of the Company, as director or officer of another corporation,
partnership, joint venture, trust, employee benefit plan, or other enterprise.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED

      Not applicable.


                                       6
<PAGE>
ITEM 8.  EXHIBITS

<TABLE>
<CAPTION>
EXHIBIT NO.                        DESCRIPTION                                     METHOD OF FILING
-----------                        -----------                                     ----------------
<S>               <C>                                                <C>
4(a)              Restated Certificate of Incorporation of the       Incorporated by reference to Form 10-Q
                  Company (September 1, 2000)                        Quarterly Report for the period ended September
                                                                     30, 2000

4(b)              By-Laws of the Company (as amended February 25,    Incorporated by reference to Form 10-Q
                  1997)                                              Quarterly Report for the period ended March 31,
                                                                     1997

4(c)              Merck & Co., Inc. Deferral Program (restated       Filed with this Registration Statement
                  October 15, 2002)

5                 Opinion and Consent of Celia A. Colbert, Vice      Filed with this Registration Statement
                  President, Secretary & Assistant General Counsel
                  of the Company

23(a)             Consent of Arthur Andersen LLP                     Omitted pursuant to Rule 437a

23(b)             Consent of Celia A. Colbert, Vice President,       Filed with this Registration Statement
                  Secretary & Assistant General Counsel of the       (included on Exhibit 5 hereto)
                  Company

24(a)             Certified Resolution of Board of Directors         Filed with this Registration Statement

24(b)             Power of Attorney                                  Filed with this Registration Statement
</TABLE>


ITEM 9. UNDERTAKINGS

      The undersigned registrant hereby undertakes:

      1. (a) To file, during any period in which offers or sales are being made,
a post-effective amendment to this registration statement:

                  (i) To include any prospectus required by Section 10(a)(3) of
            the Securities Act;

                  (ii) To reflect in the prospectus any facts or events arising
            after the effective date of this registration statement (or the most
            recent post-effective amendment thereof) which, individually or in
            the aggregate, represent a fundamental change in the information set
            forth in this registration statement;

                  (iii) To include any material information with respect to the
            plan of distribution not previously disclosed in this registration
            statement or any material change to such information in this
            registration statement;


                                       7
<PAGE>
provided, however, that paragraphs (i) and (ii) do not apply if the information
required to be included in a post-effective amendment by those paragraphs is
contained in periodic reports filed with or furnished to the SEC by the Company
pursuant to Section 13 or Section 15(d) of the Exchange Act that are
incorporated by reference in this registration statement.

            (b) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

            (c) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

      2. That, for the purpose of determining any liability under the Securities
Act, each filing of the registrant's annual report pursuant to Section 13(a) or
15(d) of the Exchange Act that is incorporated by reference in this
registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

      3. Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Company pursuant to the foregoing provisions, or otherwise, we have been advised
that, in the opinion of the SEC, such indemnification is against public policy
as expressed in the Securities Act and is, therefore, unenforceable. In the
event that a claim for indemnification against such liabilities (other than the
payment by us of expenses incurred or paid by a director, officer or controlling
person of the Company in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, we will, unless in the opinion
of our counsel the matter has been settled by controlling precedent, submit to a
court of appropriate jurisdiction the question whether such indemnification by
us is against public policy as expressed in the Securities Act and will be
governed by the final adjudication of such issue.


                                       8
<PAGE>
                                   SIGNATURES

      Pursuant to the requirements of the Securities Act, the Company certifies
that it has reasonable grounds to believe that it meets all the requirements for
filing on Form S-8, and has duly caused this registration statement to be signed
on its behalf by the undersigned, thereunto duly authorized, in Whitehouse
Station, State of New Jersey, on the 27th day of November, 2002.

                                   MERCK & CO., INC.



                                   By:          *
                                      ------------------------------------------
                                      Raymond V. Gilmartin
                                      Chairman of the Board, President and Chief
                                      Executive Officer


                                   By:/s/ Celia A. Colbert
                                      ------------------------------------------
                                      Celia A. Colbert
                                      Vice President, Secretary & Assistant
                                      General Counsel (Attorney-in-Fact)


---------------------
*     Celia A. Colbert, by signing her name hereto, does hereby sign this
      document pursuant to powers of attorney duly executed by the person named,
      filed with the SEC as an exhibit to this document, on behalf of such
      person on the date stated.


                                       9
<PAGE>
      Pursuant to the requirements of the Securities Act, this registration
statement has been signed by the following persons in the capacities and on the
dates indicated.

<TABLE>
<CAPTION>
                 SIGNATURE                                    TITLE                            DATE
                 ---------                                    -----                            ----
<S>                                           <C>                                     <C>


                      *                       Chairman, President and Chief           November 27, 2002
------------------------------------------    Executive Officer; Principal
            Raymond V. Gilmartin              Executive Officer; Director


                      *                       Executive Vice President and Chief      November 27, 2002
------------------------------------------    Financial Officer; Principal
               Judy C. Lewent                 Financial Officer


                      *                       Vice President, Controller; Principal   November 27, 2002
------------------------------------------    Accounting Officer
          Richard C. Henriques, Jr.


                      *                       Director                                November 27, 2002
------------------------------------------
             Lawrence A. Bossidy


                      *                       Director                                November 27, 2002
------------------------------------------
              William G. Bowen


                                              Director                                November 27, 2002
------------------------------------------
             Johnnetta B. Cole


                      *                       Director                                November 27, 2002
------------------------------------------
              William M. Daley


                      *                       Director                                November 27, 2002
------------------------------------------
          William B. Harrison, Jr.


                      *                       Director                                November 27, 2002
------------------------------------------
              William N. Kelley


                      *                       Director                                November 27, 2002
------------------------------------------
               Heidi G. Miller
</TABLE>


                                       10
<PAGE>
<TABLE>
<S>                                           <C>                                     <C>
                      *                       Director                                November 27, 2002
------------------------------------------
             Edward M. Scolnick


                      *                       Director                                November 27, 2002
------------------------------------------
               Thomas E. Shenk


                      *                       Director                                November 27, 2002
------------------------------------------
               Anne M. Tatlock


                      *                       Director                                November 27, 2002
------------------------------------------
               Samuel O. Thier
</TABLE>


---------------------
*     Celia A. Colbert, by signing her name hereto, does hereby sign this
      document pursuant to powers of attorney duly executed by the persons
      named, filed with the SEC as an exhibit to this document, on behalf of
      such persons, all in the capacities and on the date stated, such persons
      including a majority of the directors of the Company.


                                       11
<PAGE>
                                  EXHIBIT INDEX

<TABLE>
<CAPTION>
EXHIBIT NO.                        DESCRIPTION                                     METHOD OF FILING
-----------                        -----------                                     ----------------
<S>               <C>                                                <C>
4(a)              Restated Certificate of Incorporation of the       Incorporated by reference to Form 10-Q
                  Company (September 1, 2000)                        Quarterly Report for the period ended September
                                                                     30, 2000

4(b)              By-Laws of the Company (as amended February 25,    Incorporated by reference to Form 10-Q
                  1997)                                              Quarterly Report for the period ended March 31,
                                                                     1997

4(c)              Merck & Co., Inc. Deferral Program (restated       Filed with this Registration Statement
                  October 15, 2002)

5                 Opinion and Consent of Celia A. Colbert, Vice      Filed with this Registration Statement
                  President, Secretary & Assistant General Counsel
                  of the Company

23(a)             Consent of Arthur Andersen LLP                     Omitted pursuant to Rule 437a

23(b)             Consent of Celia A. Colbert, Vice President,       Filed with this Registration Statement
                  Secretary & Assistant General Counsel of the       (included on Exhibit 5 hereto)
                  Company

24(a)             Certified Resolution of Board of Directors         Filed with this Registration Statement

24(b)             Power of Attorney                                  Filed with this Registration Statement
</TABLE>


                                       12
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AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON NOVEMBER 27, 2002

                                                   REGISTRATION NO. 333-________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                       -----------------------------------
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
                       -----------------------------------
                                MERCK & CO., INC.
             (Exact Name of Registrant as Specified in Its Charter)
                                  P.O. BOX 100
                                 ONE MERCK DRIVE
                      WHITEHOUSE STATION, NEW JERSEY 08889
                    (Address of Principal Executive Offices)

       NEW JERSEY                                    22-1109110
(State of Incorporation)                 (I.R.S. Employer Identification Number)

                       MERCK & CO., INC. DEFERRAL PROGRAM
                            (Full Title of the Plan)

                             CELIA A. COLBERT, ESQ.
             VICE PRESIDENT, SECRETARY AND ASSISTANT GENERAL COUNSEL
                                MERCK & CO., INC.
                                  P.O. BOX 100
                                 ONE MERCK DRIVE
                      WHITEHOUSE STATION, NEW JERSEY 08889
                                 (908) 423-1000
            (Name, Address and Telephone Number of Agent for Service)

                         CALCULATION OF REGISTRATION FEE
PROPOSED MAXIMUM    PROPOSED MAXIMUM
         TITLE OF SECURITIES               AMOUNT TO BE         OFFERING PRICE         AGGREGATE          AMOUNT OF
          TO BE REGISTERED                  REGISTERED            PER SHARE       OFFERING PRICE (3)  REGISTRATION FEE
Deferred Compensation Obligations (1)      $200,000,000              100%           $200,000,000           $18,400

Common Stock, par value $.01 per
 share (2)                             1,000,000 shares (4)        $58.80           $ 58,800,000           $ 5,410
(1)   The Deferred Compensation Obligations are unsecured obligations of Merck &
      Co., Inc. to pay deferred compensation in accordance with the terms of the
      Merck & Co., Inc. Deferral Program.
(2)   Includes an indeterminate number of shares of Common Stock that may be
      issuable by reason of stock splits, stock dividends or similar
      transactions in accordance with Rule 416 under the Securities Act of 1933.

(3)   The prices stated above are estimated solely for the purpose of
      determining the registration fee and is based on the average of the high
      and low market prices of the stock as reported on the New York Stock
      Exchange listed issues on November 21, 2002.

(4)   Estimated maximum number of shares of Common Stock of Merck & Co., Inc.
      issuable during the next five years of operation of the Merck & Co., Inc.
      Deferral Program.

                                       2
PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE

      The following documents and any future filings made with the Securities
and Exchange Commission (Exchange Act File No. 1-3305) are incorporated herein
by reference:

      (a)   Current Report on Form 8-K filed on January 30, 2002;

      (b)   Current Report on Form 8-K filed on March 5, 2002 (amended by a
            Form 8-K/A filed on March 21, 2002);

      (c)   Annual Report on Form 10-K filed on March 21, 2002, for the fiscal
            year ended December 31, 2001;

      (d)   Proxy Statement filed on March 21, 2002, for the Annual Meeting of
            Stockholders held on April 23, 2002;

      (e)   Quarterly Report on Form 10-Q filed on May 13, 2002, for the quarter
            ended March 31, 2002;

      (f)   Form 11-K Annual Report filed on June 27, 2002, for the fiscal year
            ended December 31, 2001;

      (g)   Quarterly Report on Form 10-Q filed on August 13, 2002, for the
            quarter ended June 30, 2002;

      (h)   Quarterly Report on Form 10-Q filed on November 13, 2002, for the
            quarter ended September 30, 2002;

      (i)   The descriptions of the Common Stock of the registrant set forth in
            the registrant's Registration Statements pursuant to Section 12 of
            the Securities Exchange Act of 1934 (the "Exchange Act"), and any
            amendment or report filed for the purpose of updating such
            description.

      The Company's consolidated financial statements for each of the years
ended 2001, 2000 and 1999, included in the Company's Form 10-K and incorporated
by reference herein, have been audited by Arthur Andersen LLP ("Arthur
Andersen"). On February 26, 2002, the Company dismissed Arthur Andersen as its
independent public accountants and engaged PricewaterhouseCoopers LLP to serve
as the Company's independent public accountants for the fiscal year 2002. The
Company understands that the staff of the Securities and Exchange Commission
has taken the position that it will not accept consents from Arthur Andersen if
the engagement partner and the manager for the Company's audit are no longer
with Arthur Andersen. Both the engagement partner and the manager for the
Company's audit are no longer with Arthur Andersen and Arthur Andersen has
ceased practicing before the Securities and Exchange Commission. As a result,
the Company has been unable to obtain Arthur Andersen's written consent to the
incorporation by reference into this registration statement of their audit
report with respect to the Company's financial statements. Under these
circumstances, Rule 437a under the Securities Act of 1933 (the "Securities
Act") permits the Company to file this registration statement without a written
consent from Arthur Andersen. Because Arthur Andersen has not consented to the
inclusion of their report in this registration statement, Arthur Andersen will
not have any liability under Section 11(a) of the Securities Act for any untrue
statements of a material fact contained in the financial statements audited by
Arthur Andersen and incorporated by reference herein or any omission of a
material fact required to be stated therein. Accordingly, investors will not be
able to assert a claim against Arthur Andersen under Section 11(a) of the
Securities Act for any purchases of securities under this registration
statement.

ITEM 4. DESCRIPTION OF SECURITIES

      The obligations of the Company registered hereunder (the "Obligations")
are unsecured general obligations of the Company to pay the value of deferred
compensation accounts in accordance with the terms and conditions of the Merck &
Co., Inc. Deferral Program (the "Program"). The following discussion of the
Program is not a complete description of the Program and is qualified in its
entirety by the full text of the Program. The filing of this Registration
Statement on Form S-8 is not, and should not be construed as, an admission that
the Obligations constitute securities as defined by any applicable federal,
state or local law, or that registration of the Obligations is required under
any such law.

      The Program is a nonqualified deferred compensation plan for eligible
members of management (the "Participants") of the Company and its subsidiaries
and affiliates. Under the Program, the Company will provide all Participants
with the opportunity to defer income earned under various incentive plans of the
Company and certain Participants with the opportunity to defer base salary.

                                       3
The Compensation and Benefits Committee of the Board of Directors of the
Company is the administrator of the Program. Unless delegated to another party,
the administrator of the Program is responsible for determining and periodically
reviewing the investment alternatives available under the Program.

      Amounts deferred pursuant to the Program are credited to a deferred
compensation account maintained on behalf of each Participant. A Participant may
initially allocate the amounts credited to his or her deferral account among
various investment alternatives including the Company's common stock and
numerous mutual funds (as determined by the administrator). The Obligations are
adjusted to reflect the performance, whether positive or negative, of the
selected investment alternatives during the deferral period, in accordance with
the terms of the Program. Participants bear the risk that the value of the
Company's common stock, as well as that of all other investment alternatives
available under the Program, will decrease during the deferral period. The
Obligations are general unsecured and unsubordinated obligations of the Company
from time to time outstanding.

      Based on the amount of money allocated to each investment alternative,
Participants are credited with the number of full and partial shares of Company
stock or other fund that the deferred amount allocated to each alternative would
purchase based on the closing price of Company stock or the closing net asset
value of the mutual fund, respectively, on the date that the money would
otherwise have been paid as base salary or incentive compensation. Company
shares and mutual fund shares are not purchased or earmarked for a Participant's
account. A Participant's right to the Obligations cannot be transferred,
assigned, pledged or encumbered except by a written designation of a beneficiary
under the terms of the Program. There is no trading market for the Obligations.

      Participants may redesignate amounts credited to their deferred
compensation accounts among the available investment options in 1% increments at
any time. Notwithstanding the foregoing, Participants are generally not
permitted to redesignate deferred amounts (i) into common stock of the Company
or (ii) out of common stock of the Company other than amounts held in Company
stock in excess of three times base salary.

      As a general rule, at the time of the election to defer compensation, each
Participant elects (i) the time at which distribution of his or her account
balance will occur and (ii) whether such distribution will be in the form of a
lump sum payment or any number of annual installments up to a maximum of 15.
Distributions of amounts allocated to mutual funds and partial shares of Company
stock will be made in cash and distribution of amounts allocated to full shares
of Company stock will generally be made in shares of Company stock.

      The Obligations are not convertible into securities of the Company, except
that Obligations denominated as full shares of Company stock are payable as
shares of Company common stock upon distribution. The Obligations will not have
the benefit of a negative pledge or any other affirmative or negative covenant
on the part of the Company. No trustee has been appointed having the authority
to take action with respect to the Obligations, and each Participant will be
responsible for acting independently with respect to, among other things, the
giving of notices, responding to any requests for consents, waivers, or
amendments pertaining to the Obligations, enforcing covenants and taking action
upon a default.

      The Company has reserved the right to amend the Program at any time,
except that no such amendment shall adversely affect the right of each
Participant to the amounts credited to his or her deferred compensation account
as of the date of the amendment.

                                       4
ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL

      The legality of the securities offered pursuant to this Registration
Statement will be passed upon for the Company by Celia A. Colbert, Esq., Vice
President, Secretary and Assistant General Counsel of the Company.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS

      The New Jersey Business Corporation Act provides that a New Jersey
corporation has the power to indemnify a director or officer against his or her
expenses and liabilities in connection with any proceeding involving the
director or officer by reason of his or her being or having been such a director
or officer, other than a proceeding by or in the right of the corporation, if
such a director or officer acted in good faith and in a manner he or she
reasonably believed to be in or not opposed to the best interests of the
corporation; and with respect to any criminal proceeding, such director or
officer had no reasonable cause to believe his or her conduct was unlawful.

      The indemnification and advancement of expenses shall not exclude any
other rights, including the right to be indemnified against liabilities and
expenses incurred in proceedings by or in the right of the corporation, to which
a director or officer may be entitled under a certificate of incorporation,
bylaw, agreement, vote of stockholders, or otherwise; provided that no
indemnification shall be made to or on behalf of a director or officer if a
judgment or other final adjudication adverse to the director or officer
establishes that his or her acts or omissions (a) were in breach of his or her
duty of loyalty to the corporation or its stockholders, (b) were not in good
faith or involved a knowing violation of law or (c) resulted in receipt by the
director or officer of an improper personal benefit.

      The Company's Restated Certificate of Incorporation provides that, to the
fullest extent permitted by the laws of the State of New Jersey, directors and
officers of the Corporation shall not be personally liable to the Corporation or
its stockholders for damages for breach of any duty owed to the Corporation or
its stockholders, except that a director or officer shall not be relieved from
liability for any breach of duty based upon an act or omission (a) in breach of
such person's duty of loyalty to the Corporation or its stockholders, (b) not in
good faith or involving a knowing violation of law or (c) resulting in receipt
by such person of an improper personal benefit.

      The By-Laws of the Company provide that a former, present or future
director, officer or employee of the Company or the legal representative of any
such director, officer or employee shall be indemnified by the Company: (a)
against reasonable costs, disbursements and counsel fees paid or incurred where
such person has been successful in the defense on the merits or otherwise of any
pending, threatened or completed civil, criminal, administrative or arbitrative
action, suit or proceeding, and any appeal therein and any inquiry or
investigation which could lead to such action, suit, or proceeding, or in the
defense of any claim, issue, or matter therein, brought by reason of such
person's being or having been such director, officer or employee, and (b) with
respect to the defense of any such action, suit, proceeding, inquiry or
investigation for which indemnification is not made under (a) above, against
reasonable costs, disbursements (which shall include amounts paid in
satisfaction of settlements, judgments, fines and penalties, exclusive, however,
of any amount paid or payable to the Company) and counsel fees if such person
acted in good faith and in a manner such person reasonably believed to be in or
not opposed to the best interests of the Company, and in connection with any
criminal proceedings such person also had no reasonable cause to believe the
conduct was unlawful, with the determination as to whether the applicable
standard of conduct was met to be made by a majority of the members of the Board
of Directors (sitting as a Committee of the Board) who were not parties to such
inquiry, investigation, action, suit or proceeding or by any one or more
disinterested counsel to whom the

                                       5
question may be referred by the Board of Directors; provided, however, in
connection with any proceeding by or in the right of the Company, no
indemnification shall be provided as to any person adjudged by any court to be
liable to the Company except as and to the extent determined by such court.

      The Company enters into indemnification agreements with its directors and
officers and enters into insurance agreements on its own behalf. The
indemnification agreements provide that the Company agrees to hold harmless and
indemnify its directors and officers to the fullest extent authorized or
permitted by the Business Corporation Act of the State of New Jersey, or any
other applicable law, or by any amendment thereof or other statutory provisions
authorizing or permitting such indemnification that is adopted after the date
hereof. Without limiting the generality of the foregoing, the Company agrees to
hold harmless and indemnify its directors and officers to the fullest extent
permitted by applicable law against any and all expenses, judgments, fines, and
amounts paid in settlement actually and reasonably incurred by its directors and
officers in connection with the defense of any present or future threatened,
pending, or completed claim, action, suit, or proceeding by reason of the fact
that they were, are, shall be, or shall have been a director or officer of the
Company, or are or were serving, shall serve, or shall have served, at the
request of the Company, as director or officer of another corporation,
partnership, joint venture, trust, employee benefit plan, or other enterprise.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED

      Not applicable.

                                       6
ITEM 8.  EXHIBITS
EXHIBIT NO.                        DESCRIPTION                                     METHOD OF FILING
-----------                        -----------                                     ----------------
4(a)              Restated Certificate of Incorporation of the       Incorporated by reference to Form 10-Q
                  Company (September 1, 2000)                        Quarterly Report for the period ended September
                                                                     30, 2000

4(b)              By-Laws of the Company (as amended February 25,    Incorporated by reference to Form 10-Q
                  1997)                                              Quarterly Report for the period ended March 31,
                                                                     1997

4(c)              Merck & Co., Inc. Deferral Program (restated       Filed with this Registration Statement
                  October 15, 2002)

5                 Opinion and Consent of Celia A. Colbert, Vice      Filed with this Registration Statement
                  President, Secretary & Assistant General Counsel
                  of the Company

23(a)             Consent of Arthur Andersen LLP                     Omitted pursuant to Rule 437a

23(b)             Consent of Celia A. Colbert, Vice President,       Filed with this Registration Statement
                  Secretary & Assistant General Counsel of the       (included on Exhibit 5 hereto)
                  Company

24(a)             Certified Resolution of Board of Directors         Filed with this Registration Statement

24(b)             Power of Attorney                                  Filed with this Registration Statement
ITEM 9. UNDERTAKINGS

      The undersigned registrant hereby undertakes:

      1. (a) To file, during any period in which offers or sales are being made,
a post-effective amendment to this registration statement:

                  (i) To include any prospectus required by Section 10(a)(3) of
            the Securities Act;

                  (ii) To reflect in the prospectus any facts or events arising
            after the effective date of this registration statement (or the most
            recent post-effective amendment thereof) which, individually or in
            the aggregate, represent a fundamental change in the information set
            forth in this registration statement;

                  (iii) To include any material information with respect to the
            plan of distribution not previously disclosed in this registration
            statement or any material change to such information in this
            registration statement;

                                       7
provided, however, that paragraphs (i) and (ii) do not apply if the information
required to be included in a post-effective amendment by those paragraphs is
contained in periodic reports filed with or furnished to the SEC by the Company
pursuant to Section 13 or Section 15(d) of the Exchange Act that are
incorporated by reference in this registration statement.

            (b) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

            (c) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

      2. That, for the purpose of determining any liability under the Securities
Act, each filing of the registrant's annual report pursuant to Section 13(a) or
15(d) of the Exchange Act that is incorporated by reference in this
registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

      3. Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Company pursuant to the foregoing provisions, or otherwise, we have been advised
that, in the opinion of the SEC, such indemnification is against public policy
as expressed in the Securities Act and is, therefore, unenforceable. In the
event that a claim for indemnification against such liabilities (other than the
payment by us of expenses incurred or paid by a director, officer or controlling
person of the Company in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, we will, unless in the opinion
of our counsel the matter has been settled by controlling precedent, submit to a
court of appropriate jurisdiction the question whether such indemnification by
us is against public policy as expressed in the Securities Act and will be
governed by the final adjudication of such issue.

                                       8
SIGNATURES

      Pursuant to the requirements of the Securities Act, the Company certifies
that it has reasonable grounds to believe that it meets all the requirements for
filing on Form S-8, and has duly caused this registration statement to be signed
on its behalf by the undersigned, thereunto duly authorized, in Whitehouse
Station, State of New Jersey, on the 27th day of November, 2002.

                                   MERCK & CO., INC.

                                   By:          *
                                      ------------------------------------------
                                      Raymond V. Gilmartin
                                      Chairman of the Board, President and Chief
                                      Executive Officer

                                   By:/s/ Celia A. Colbert
                                      ------------------------------------------
                                      Celia A. Colbert
                                      Vice President, Secretary & Assistant
                                      General Counsel (Attorney-in-Fact)

---------------------
*     Celia A. Colbert, by signing her name hereto, does hereby sign this
      document pursuant to powers of attorney duly executed by the person named,
      filed with the SEC as an exhibit to this document, on behalf of such
      person on the date stated.

                                       9
Pursuant to the requirements of the Securities Act, this registration
statement has been signed by the following persons in the capacities and on the
dates indicated.
SIGNATURE                                    TITLE                            DATE
                 ---------                                    -----                            ----
*                       Chairman, President and Chief           November 27, 2002
------------------------------------------    Executive Officer; Principal
            Raymond V. Gilmartin              Executive Officer; Director

                      *                       Executive Vice President and Chief      November 27, 2002
------------------------------------------    Financial Officer; Principal
               Judy C. Lewent                 Financial Officer

                      *                       Vice President, Controller; Principal   November 27, 2002
------------------------------------------    Accounting Officer
          Richard C. Henriques, Jr.

                      *                       Director                                November 27, 2002
------------------------------------------
             Lawrence A. Bossidy

                      *                       Director                                November 27, 2002
------------------------------------------
              William G. Bowen

                                              Director                                November 27, 2002
------------------------------------------
             Johnnetta B. Cole

                      *                       Director                                November 27, 2002
------------------------------------------
              William M. Daley

                      *                       Director                                November 27, 2002
------------------------------------------
          William B. Harrison, Jr.

                      *                       Director                                November 27, 2002
------------------------------------------
              William N. Kelley

                      *                       Director                                November 27, 2002
------------------------------------------
               Heidi G. Miller
10
*                       Director                                November 27, 2002
------------------------------------------
             Edward M. Scolnick

                      *                       Director                                November 27, 2002
------------------------------------------
               Thomas E. Shenk

                      *                       Director                                November 27, 2002
------------------------------------------
               Anne M. Tatlock

                      *                       Director                                November 27, 2002
------------------------------------------
               Samuel O. Thier
---------------------
*     Celia A. Colbert, by signing her name hereto, does hereby sign this
      document pursuant to powers of attorney duly executed by the persons
      named, filed with the SEC as an exhibit to this document, on behalf of
      such persons, all in the capacities and on the date stated, such persons
      including a majority of the directors of the Company.

                                       11
EXHIBIT INDEX
EXHIBIT NO.                        DESCRIPTION                                     METHOD OF FILING
-----------                        -----------                                     ----------------
4(a)              Restated Certificate of Incorporation of the       Incorporated by reference to Form 10-Q
                  Company (September 1, 2000)                        Quarterly Report for the period ended September
                                                                     30, 2000

4(b)              By-Laws of the Company (as amended February 25,    Incorporated by reference to Form 10-Q
                  1997)                                              Quarterly Report for the period ended March 31,
                                                                     1997

4(c)              Merck & Co., Inc. Deferral Program (restated       Filed with this Registration Statement
                  October 15, 2002)

5                 Opinion and Consent of Celia A. Colbert, Vice      Filed with this Registration Statement
                  President, Secretary & Assistant General Counsel
                  of the Company

23(a)             Consent of Arthur Andersen LLP                     Omitted pursuant to Rule 437a

23(b)             Consent of Celia A. Colbert, Vice President,       Filed with this Registration Statement
                  Secretary & Assistant General Counsel of the       (included on Exhibit 5 hereto)
                  Company

24(a)             Certified Resolution of Board of Directors         Filed with this Registration Statement

24(b)             Power of Attorney                                  Filed with this Registration Statement
12