Methylecgonidine

Methylecgonidine (anhydromethylecgonine; anhydroecgonine methyl ester; AEME) is a chemical intermediate derived from ecgonine or cocaine.

Methylecgonidine is a pyrolysis product formed when crack cocaine is smoked, making this substance a useful biomarker to specifically test for use of crack cocaine, as opposed to powder cocaine which does not form methylecgonidine as a metabolite. Methylecgonidine has a relatively short half-life of 18-21 minutes, after which it is metabolised to ecgonidine, meaning that the relative concentrations of the two compounds can be used to estimate how recently crack cocaine has been smoked. Methylecgonidine has been shown to be specifically more harmful to the body than other byproducts of cocaine; for example to the heart, lungs & liver. The toxicity is due to a partial agonist effect at M1 and M3 muscarinic receptors, leading to DNA fragmentation and neuronal death by apoptosis.