A number of studies have shown that selective serotonin reuptake inhibitors (SSRIs) like Prozac prevent MDMA's neurotoxic effect. The theory as to why this happens is this: SSRIs plug the reuptake transporters, thus preventing dopamine from getting into the serotonin axon terminal (see the previous slide). Notice that the prozac fits pefectly into the transporter. Researchers refer to this as "affinity" and say that prozac has a greater affinity for the uptake transporter than other things in the synapse, including serotonin. In other words, Prozac will bind to the transporter first. It will also stay there for a relatively long time. Prozac has a half-life of 30 hours, which means it takes 30 hours for half of it to leave your body, another 30 hours for half of what's left to leave, etc. It is thus called a "long-acting" SSRI. It plugs the transporters for a longer period of time than the other common SSRIs do. Research has shown that brain serotonin levels remain significantly depleted for approximately 24 hours after a lage dose of MDMA. It is during this time period (beween 6 and 24 hours after dosing) that the brain's serotonin transporters are left empty and vulnerable, and it is during this time that the neurotoxic damage occurs. This means Prozac may be more effective at preventing MDMA neurotoxicity than other SSRIs, which do not last as long in the body (although this is unknown).

An important observation in these studies was that prozac prevented the neurotoxic damage even when given up to six hours after the MDMA. What they did was inject all the animals with MDMA, and then every hour they gave some of them an injection of Prozac. Only the animals who got the Prozac during the first six hours showed no damage. The ones who got the Prozac on the seventh, eighth, ninth and tenth hours (etc.) sustained damage, with the ones who got the prozac later sustaining more.

While no studies have been done to assess the effectiveness of Prozac as a neuro-protective agent against MDMA neurotoxicity in humans, there is no reason to suspect that human brains react differently than animal brains in this regard.

Next let's take a look at how Ecstasy actually enters the serotonin cell...