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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-05-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001145404</issuerCik>
        <issuerName>CORNERSTONE THERAPEUTICS INC</issuerName>
        <issuerTradingSymbol>CRTX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001492466</rptOwnerCik>
            <rptOwnerName>Vecchia Marco</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CHIESI FARMACEUTICI SPA</rptOwnerStreet1>
            <rptOwnerStreet2>VIA PALERMO 26/A</rptOwnerStreet2>
            <rptOwnerCity>PARMA</rptOwnerCity>
            <rptOwnerState>L6</rptOwnerState>
            <rptOwnerZipCode>L643122</rptOwnerZipCode>
            <rptOwnerStateDescription>ITALY</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option to Purchase Common Stock (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>5.97</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-05-20</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>15000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2020-05-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>15000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Shares subject to these options vest in 36 approximately equal monthly installments with the first installment vesting as of June 20, 2010. These options were granted pursuant to the terms of Cornerstone Therapeutics Inc. Amended and Restated Non-Employee Director Compensation and Reimbursement Policy, effective October 31, 2008.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ David Price, attorney in fact for Marco Vecchia pursuant to a power of attorney</signatureName>
        <signatureDate>2010-05-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
