Please Scroll Down to See Forums Below 
I believe you mean agonist, right? Wellbutrin is a very mild dopamine reuptake inhibtor (at much higher dosages it also promotes some dopamine release as well). It is also marketed as zyban for reducing one's cravings when attempting to stop smoking (there is an unidentified MAOI in cigarette smoke which many researchers believe is responsible for their addictive qualities). This is a pretty common adjunct to SSRI treatment when patients begin to complain of the weight-gain, lethargy, apathy, and loss of sex drive which "treatement" with these drugs often result in. The way SSRIs work to treat depression is by blunting one's emotions and feelings - this is why many people complain of "feeling hollow" while taking them.
IMHO, most of these drugs suck, plain and simple. The reasons for their pervasiveness in modern medicine are a combination of ignorance, bureacracy, and plain old american greed. First of all, GP's hand out scripts for them like candy since they are nonscheduled. The FDA freely allows the pharmaceutical gaints to release new and potentially dangerous SSRIs (read: paxil) for a broad range of ambigous pseudo-psychiatric disorders primarily becuase of the neurotransmitter which they affect. In simple terms, boosting ones levels of serotonin cannot get you "high" (and don't mention MDMA, becuase there is more invloved there than serotonergic release). The FDA and DEA both like the fact that these drugs have no "abuse potential". You see, the problem with effective treatment for bona fide depression lies in the fact that any effective remedy will in fact have some "abuse potential". This is because to treat depression quickly and effectively, you must target a different neurtransmitter - DOPAMINE. Think about it, every major hard drug is a big time dopamine agonist (cocaine is a reuptake inhibtor, amphetamines produce a powerful prolonged release, opiates mimic dopamine at the receptor levels with chemicals called endorphins, even pot has some mild dopaminergic properties). Wellbutrin is at best, an extremely mild dopaminergic drug. If it was even remotely effective at prolonging or reducing DA uptake, you can bet your ass it would be scheduled. There have been extensive studies done on the subject and the result is clear - dopaminerigic augmentation is the key to real meaningful depression abatement. Your lawmakers are not interested in that, they are much more comfortable with passing along stop-gap, dehumanizing drugs simply becuase no one can (or would want to) abuse such chemicals. The politics surrounding dopamine are very much like those of anabolic steroids - fear, mistrust, ignorance, and plain stupidity.
