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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-04-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000057055</issuerCik>
        <issuerName>KV PHARMACEUTICAL CO /DE/</issuerName>
        <issuerTradingSymbol>KVA / KVB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001039209</rptOwnerCik>
            <rptOwnerName>HERMELIN MARC S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2503 S. HANLEY ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ST. LOUIS</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>63144</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman &amp;  CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common</value>
            </securityTitle>
            <transactionDate>
                <value>2007-04-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionTimeliness>
                <value>E</value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3009</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1311565</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Deemed indirect beneficial owner as trustee solely because beneficiary is a sibling of the trustee.</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Such shares of Class A Common are held in one Trust, of which the reporting person is one of three trustees, under Trust Agreement dated 12/22/73 fbo Anne S. Kirschner, sister of reporting person.</footnote>
        <footnote id="F2">Distribution to beneficiary of Trust without consideration.</footnote>
        <footnote id="F3">Does not include: (a) 67,630 shares of Class A Common Stock indirectly held in a limited partnership; (b) 1,856,690 shares of Class A Common Stock which are held in two trusts, in each of which the reporting person is one of three trustees, including (i) Trust under Trust Agreement dated 12/22/73 fbo Marc S. Hermelin, under which the reporting person is the primary beneficiary, and (ii) Trust under Trust Agreement dated 12/23/73 fbo Minnette Hermelin, under which the reporting person is also a beneficiary; (c) 2,637,085 shares of Class B Common Stock indirectly owned by the three trustees, including (i) Trust under Trust Agreement dated 12/22/73 fbo Marc S. Hermelin, under which the reporting person is the primary beneficiary, and (ii) Trust under Trust Agreement dated 12/23/73 fbo Minnette Hermelin, under which the reporting person is also a beneficiary; and (d) 69,668 shares of Class B Common Stock indirectly owned by the reporting person that are held in a limited partnership.</footnote>
        <footnote id="F4">Does not include (a) 1,247,586 shares of Class A Common Stock which are held in one Trust under Trust Agreement dated 12/22/73 fbo Arnold Hermelin, under which the reporting person is deemed to have indirect beneficial ownership solely because the beneficiary is a sibling of the Trustee; and (b) 4,159,687 shares of Class B Common Stock which are held in two trusts, including (i) Trust Agreement dated 12/22/73 fbo Arnold Hermelin, and (ii) Trust under Trust Agreement dated 12/22/73 fbo Anne Kirschner, under both of which the reporting person is deemed to have indirect beneficial ownership solely because the beneficiaries are siblings of the Trustee.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Marc S. Hermelin</signatureName>
        <signatureDate>2007-04-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
