Rectal administration of nicomorphine in patients improves biological availability of morphine and its glucuronide conjugates

Towards identifying nicomorphine administration in doping control: synthesis of metabolites

Aim: Nicomorphine is rapidly metabolized mainly to the biologically active 6-nicotinoyl morphine and morphine. In sport, morphine and nicomorphine use is prohibited whereas codeine use is permitted. Accredited laboratories routinely test for morphine hence must be able to distinguish morphine, as a metabolite of a prohibited substance, from that whose use is permitted. Results: Here we show a relatively simple method to synthesize the nicomorphine metabolites, 3-nicotinoyl and 6-nicotinoyl morphine, and indicate how they may be used to identify nicomorphine administration. Conclusion: This approach should help confirm that it is not codeine, an allowable analgesic in sport, that has been administered.