text: prozac and other drugs? just wondering what can happen to you if you take prozac (fluoxetine) with other 'non-prescription' drugs i.e: ecstacy, speed, marijuana? what effect can this have on the body? can it kill you or cause major problems? if only illegal drugs came in packets with instructions on the outside. we'd all know exactly what the drug would do, how much is too much and what other drugs are to be avoided at the same time.  unfortunately they don't. and while it's relatively easy to find out about the various effects of illegal drugs it's less easy to find out about safe amounts or dangerous combinations.  mixing drugs isn't a good idea. it makes the effects unpredictable and the risks harder to define.