Objectives: To assess whether 1) the necessary drug classes and 2) the necessary drug-class membership relations are represented in biomedical terminologies in order to support clinical decision regarding drug-drug interactions.
Methods: In order to investigate drug classes and drug-class membership in clinical terminologies, we start by establishing a reference list of these entities. Then, we map drugs and classes to the UMLS, where we investigate their relations.
Results: 186 (83%) of the 223 names for drug classes mapped to the UMLS. The single best source is SNOMED CT with 75%. 140 (89%) of the 157 drug-membership relations were found in the UMLS.
Conclusions: One important category of drug classes missing from all clinical terminologies is related to drug metabolism by the Cytochrome P450 enzyme family.