Pharmacokinetics of intravenously administered nicomorphine and its metabolites in man.

Intravenous doses of 30, 20 and 10 mg nicomorphine (Vilan) are extremely quickly metabolized into the metabolites 6-nicotinoylmorphine and morphine. The half-lives of elimination are respectively 3 min for nicomorphine, 3 and 15 min for 6-nicotinoylmorphine, and 135-190 min for morphine. The kinetics of the 30 and 20 mg dose are comparable, the 10 mg dose shows patient dependent variations in metabolism. The AUC of the parent drug and its metabolites is linearly related to the dose.