The piperazines are a large group of chemicals. The focus here will be on the recreationally used derivatives, that is the benzylpiperazines (i.e.BZP) and the methylenedioxy derivatives (e.g. TFMPP, mCPP, MeOPP), the latter being most similar to MDMA as its name suggests.
There is very little pharmacological research on this group currently, and most of the studies that do exist look predominantly at bzp, tfmpp, mcpp as these are the most commonly used substances.
BZP: acts to increase serotonin in the central nervous system and prefers serotonin 5-ht type 1 receptors. This gives the user the amphetamine-like effects that are commonly noted when taking BZP.
TFMPP: also interacts with the serotonergic system through 5-ht type 1 and type 2 receptors. It is considered 3 times less potent than MDMA at increasing serotonin by inhibiting its reuptake (see MDMA sectiom for more details on this).
BZP + TFMPP: these two substances seem to work synergistically in the central nervous system. Even at low doses, they increase levels of serotonin and dopamine parallel to each other mimicking the effects seen in MDMA. Some studies have even shown that at higher doses of both drugs, a greater level of dopamine is produced than the drug on its own.
mCPP: interacts with a wider array of receptors and transmitters, mainly serotonin, adrenaline and dopamine. This is why the euphoric and hallucinogenic effects are seen to be similar to MDMA. mCPP may also cause serotonin syndrome (see MDMA section). This is a very high level of serotonin build up which causes the user to experience fever-like symptoms and can sometimes be fatal.