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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2022-01-06</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000883984</issuerCik>
        <issuerName>ICU MEDICAL INC/DE</issuerName>
        <issuerTradingSymbol>ICUI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001326143</rptOwnerCik>
            <rptOwnerName>SMITHS GROUP PLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>11-12 ST JAMES'S SQUARE</rptOwnerStreet1>
            <rptOwnerStreet2>4TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>LONDON</rptOwnerCity>
            <rptOwnerState>X0</rptOwnerState>
            <rptOwnerZipCode>SW1Y 4LB</rptOwnerZipCode>
            <rptOwnerStateDescription>UNITED KINGDOM</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2500000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Smiths Group International Holdings Limited</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares are held directly by Smiths Group International Holdings Limited (&quot;SGIH&quot;). SGIH is a wholly owned subsidiary of Smiths Group plc (&quot;SGP&quot;). SGP is an indirect beneficial owner of the shares.</footnote>
    </footnotes>

    <remarks>Reporting Owner Name/Address/Relationship to Issuer: Smiths Group plc (SGP), 4th Floor, 11-12 St James's Square, London, England SW1Y 4LB; 10% Ownership; Smiths Group International Holdings Limited (SGIH), 4th Floor, 11-12 St James's Square, London, England SW1Y 4LB; 10% Ownership.</remarks>

    <ownerSignature>
        <signatureName>/s/ Smiths Groups plc, Matthew John Whyte, Attorney-in-Fact</signatureName>
        <signatureDate>2022-01-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
