[In vitro interaction of selegiline, riboflavin and light. Sensitized photodegradation of drugs. I].

Selegiline (Deprenyl, Jumex, Movergan etc.) is primarily used in the therapy of Parkinson's disease due to its neuroprotective, antidepressive and oxidative stress-preventing activities. Its prime effect is based upon the inhibition of the monoamine oxidase enzyme (MAO-B). The cofactor of this flavoenzyme is riboflavin (vitamin B2). Riboflavin, on the other hand, is an effective photosensitizer, with the capacity to promote the photodegradation of molecules (drugs, biological systems) which are otherwise stable against daylight. It has been studied whether this property of riboflavin is expressed against selegiline as well. This experiments proved that in the presence of riboflavin, both daylight and the light of daylight-lamps are sufficient to significantly decompose selegiline. The major decomposition product is methamphetamine.