Para-Methoxymethamphetamine

para-Methoxymethamphetamine (PMMA), also known as 4-methoxy-N-methylamphetamine (4-MMA), is a serotonergic drug of the amphetamine family related to para-methoxyamphetamine (PMA). It is the 4-methoxy analogue of methamphetamine. Little is known about the pharmacological properties, metabolism, and toxicity of PMMA; because of its structural similarity to PMA, which has known toxicity in humans, it is thought to have considerable potential to cause harmful side effects or death in overdose. In the early 2010s, a number of deaths in users of the drug MDMA were linked to misrepresented tablets and capsules of PMMA.

PMMA is a serotonin–norepinephrine releasing agent (SNRA) as well as potent monoamine oxidase inhibitor (MAOI). Its effects in humans are reputedly similar to those of PMA, but slightly more empathogenic in nature. It has a reduced tendency to produce severe hyperthermia at low dosages, but at higher dosages side effects and risk of death become similar to those of PMA.

The synthesis and effects of PMMA were described by American experimental chemist Alexander Shulgin in his book PiHKAL, where it is referred to by the name "methyl-MA", as the N-methylated form of 4-MA (PMA).