I can confirm with the HL7 Pharmacy Working Group, but clinically, there is a subtle nuance between "Medication not effective" and "lack of drug action / ineffective drug action". The proposed equivalence could be true if a medication had only one active ingredient. In combination drugs which contain multiple active ingredients, each with their specific drug action, it is possible to have a situation where one of the intended actions of the combo drug was ineffective, but the overall therapeutic effect for the entire combo drug was effective. Proposed resolution: Not Persuasive.