The muscarinic effect of anhydroecgonine methyl ester, a crack cocaine pyrolysis product, impairs melatonin synthesis in the rat pineal gland.

Anhydroecgonine methyl ester (AEME), also called methylecgonidine, is a pyrolysis product of crack cocaine that is neurotoxic and potentiates cocaine-induced sensitization. The sensitization induced by drugs of abuse can be influenced by melatonin, a neuroprotective pineal hormone. In the same way, drugs of abuse like alcohol and methamphetamine can modify melatonin synthesis.