In fact, Meridia, a weight
drug, is an SNRI. Another SNRI, Effexor, has no weight
properties, but it is an antidepressant. This shows that tiny changes in chemical structure can have big effects on the brain.
I take Wellbutrin which is a SNRI, I have no loss of sex drive what so ever, and while I have put on weight I don't think it is related to the drug. I think it is related to my eating habits in that I eat crap all the time and need to knock that out of my diet.