"No alteplase" is an intended exposure concept that may be used in expressing what an Evidence is about.

<status value="draft"/><description value="no alteplase"/><actual value="false"/><characteristic><description value="no alteplase"/><exclude value="true"/><definitionCodeableConcept><coding><system value="http://www.nlm.nih.gov/research/umls/rxnorm"/><code value="8410"/><display value="alteplase"/></coding></definitionCodeableConcept></characteristic></EvidenceVariable>