<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3/A</documentType>

    <periodOfReport>2005-06-27</periodOfReport>

    <dateOfOriginalSubmission>2005-07-01</dateOfOriginalSubmission>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001000736</issuerCik>
        <issuerName>CAREMARK RX INC</issuerName>
        <issuerTradingSymbol>CMX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001331844</rptOwnerCik>
            <rptOwnerName>Spalding William R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>211 COMMERCE STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 800</rptOwnerStreet2>
            <rptOwnerCity>NASHVILLE</rptOwnerCity>
            <rptOwnerState>TN</rptOwnerState>
            <rptOwnerZipCode>37201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP Strategic Development</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <remarks>Amendment of Form 3 to attach Power of Attorney as an exhibit.</remarks>

    <ownerSignature>
        <signatureName>/s/ William R. Spalding</signatureName>
        <signatureDate>2005-08-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
