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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 Hfmj8ISQVkc+acdAuAmjCIiEFSd6mRkGYWaiAHxshQK3D1q1pscW/afMOkMhyTHl
 z4XUC8JTbrVzp2zyoNnFmg==

<SEC-DOCUMENT>0001140361-10-033010.txt : 20100812
<SEC-HEADER>0001140361-10-033010.hdr.sgml : 20100812
<ACCEPTANCE-DATETIME>20100812131055
ACCESSION NUMBER:		0001140361-10-033010
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100810
FILED AS OF DATE:		20100812
DATE AS OF CHANGE:		20100812

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Wallman Amy
		CENTRAL INDEX KEY:			0001291183

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08269
		FILM NUMBER:		101010414

	MAIL ADDRESS:	
		STREET 1:		320 ROYAL TERN ROAD SOUTH
		CITY:			PONTE VEDRA BEACH
		STATE:			FL
		ZIP:			32082

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			OMNICARE INC
		CENTRAL INDEX KEY:			0000353230
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-DRUG STORES AND PROPRIETARY STORES [5912]
		IRS NUMBER:				311001351
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		100 E RIVERCENTER BLVD
		STREET 2:		STE 1600
		CITY:			COVINGTON
		STATE:			KY
		ZIP:			41101
		BUSINESS PHONE:		6063923300

	MAIL ADDRESS:	
		STREET 1:		100 E RIVERCENTER BLVD
		STREET 2:		STE 1600
		CITY:			COVINGTON
		STATE:			KY
		ZIP:			41101
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-08-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000353230</issuerCik>
        <issuerName>OMNICARE INC</issuerName>
        <issuerTradingSymbol>OCR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001291183</rptOwnerCik>
            <rptOwnerName>Wallman Amy</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>100 E. RIVERCENTER BLVD.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>COVINGTON</rptOwnerCity>
            <rptOwnerState>KY</rptOwnerState>
            <rptOwnerZipCode>41011</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-08-10</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>20.23</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>34315</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The purchase price represents the weighted average purchase price ranging in price from $20.13 to $20.32.  The number of shares purchased at each separate price will be made available to the SEC staff, the issuer, or a security holder of the issuer upon request.</footnote>
        <footnote id="F2">Incudes 2,439 shares acquired in exempt transactions under the Omnicare StockPlus Program (broad-based stock purchase/option plan).</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Thomas R. Marsh, attorney-in-fact for Amy Wallman</signatureName>
        <signatureDate>2010-08-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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