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        <submissionType>144</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001611311</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0001437402</issuerCik>
            <issuerName>ARDELYX INC</issuerName>
            <secFileNumber>001-36485</secFileNumber>
            <issuerAddress>
                <ns2:street1>400 Fifth Avenue</ns2:street1>
                <ns2:city>Waltham</ns2:city>
                <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                <ns2:zipCode>02451</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>5107451700</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>DAVID P ROSENBAUM </nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>49564</noOfUnitsSold>
            <aggregateMarketValue>315227.04</aggregateMarketValue>
            <noOfUnitsOutstanding>235428183</noOfUnitsOutstanding>
            <approxSaleDate>09/27/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>12/31/2018</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock Units</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>29564</amountOfSecuritiesAcquired>
            <paymentDate>12/31/2018</paymentDate>
            <natureOfPayment>N/A</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>09/27/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>20000</amountOfSecuritiesAcquired>
            <paymentDate>09/27/2024</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>DAVID P ROSENBAUM TODSUBJECT TO STA RULES</name>
                <address>
                    <ns2:street1>400 Fifth Avenue</ns2:street1>
                    <ns2:city>Waltham</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02451</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>09/13/2024</saleDate>
            <amountOfSecuritiesSold>5312</amountOfSecuritiesSold>
            <grossProceeds>33253.12</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>DAVID P ROSENBAUM TODSUBJECT TO STA RULES</name>
                <address>
                    <ns2:street1>400 Fifth Avenue</ns2:street1>
                    <ns2:city>Waltham</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02451</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>08/20/2024</saleDate>
            <amountOfSecuritiesSold>27726</amountOfSecuritiesSold>
            <grossProceeds>165345.34</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for DAVID P ROSENBAUM </name>
                <address>
                    <ns2:street1>400 Fifth Avenue</ns2:street1>
                    <ns2:city>Waltham</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02451</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>08/19/2024</saleDate>
            <amountOfSecuritiesSold>18700</amountOfSecuritiesSold>
            <grossProceeds>111038.73</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for DAVID P ROSENBAUM </name>
                <address>
                    <ns2:street1>400 Fifth Avenue</ns2:street1>
                    <ns2:city>Waltham</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02451</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>08/16/2024</saleDate>
            <amountOfSecuritiesSold>1300</amountOfSecuritiesSold>
            <grossProceeds>7698.21</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>09/27/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>05/17/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ David P Rosenbaum</signature>
        </noticeSignature>
    </formData>
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144
0001611311
XXXXXXXX
LIVE
0001437402
ARDELYX INC
001-36485
400 Fifth Avenue
Waltham
MA
02451
5107451700
DAVID P ROSENBAUM
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
49564
315227.04
235428183
09/27/2024
NASDAQ
Common
12/31/2018
Restricted Stock Units
Issuer
N
29564
12/31/2018
N/A
Common
09/27/2024
Exercise of Stock Options
Issuer
N
20000
09/27/2024
Cash
N
DAVID P ROSENBAUM TODSUBJECT TO STA RULES
400 Fifth Avenue
Waltham
MA
02451
Common
09/13/2024
5312
33253.12
DAVID P ROSENBAUM TODSUBJECT TO STA RULES
400 Fifth Avenue
Waltham
MA
02451
Common
08/20/2024
27726
165345.34
10b5-1 Sales for DAVID P ROSENBAUM
400 Fifth Avenue
Waltham
MA
02451
Common
08/19/2024
18700
111038.73
10b5-1 Sales for DAVID P ROSENBAUM
400 Fifth Avenue
Waltham
MA
02451
Common
08/16/2024
1300
7698.21
09/27/2024
05/17/2024
/s/ David P Rosenbaum