[Nitrosatable drugs (author's transl)]

Out of 61 drugs, considered to be potentially nitrosatable on the basis of their chemical structure and being used for oral administration in the GDR, ten (Aminophenazone, Ampicilline, Clomipramine, Desipramine, Ethambutole, Imipramine, Noramidopyrinemethansulfonate, Oxacilline, Phenoxymethylpenicilline, Piperazine) have been nitrosated in vitro under simulated conditions of the human stomach. Each compound demonstrated an individual nitrosation behaviour. Only two of the N-nitrosocompounds formed could be identified as well known carcinogens. The chemical structure of the others are unknown yet. Using ascorbic acid as inhibitor, an inhibition of nitrosation could be reached in all cases, but even with high amounts the inhibition was not complete. In order to exclude or, least to diminish a possible carcinogenic risk of endogenically formed N-nitrosocompounds from drugs to humans, drugs orally administered and forming carcinogenic N-nitrosocompounds should be replaced by non-nitrosatable ones. Formulations of all other nitrosatable drugs should contain sufficient amounts of ascorbic acid, provided, that the pharmacological quality of the drug is not deteriorated to any greater extent.