It is pointless to take a psych drug while taking abusing your drug of choice. Many say it can be dangerous, as you are already supplying your body with more than it needs to be happy, with drugs. Add prozac to it, or any other psych med, and you are just throwing your body into mayhem. It's bad enough to mix benzos and opiates, as many have died from this lethal combination. Plus, if you think w/d from opiates is bad, just wait till you see what a benzo w/d will do to a person.
For what its worth, I can tell you that Ive been taking prozac, xanax, morphine, hydrocodone and several other medications that I am prescribed all together every morning and evening and it hasnt affected me. I cant tell that I take the meds. But to each his own. Everyone reacts differently. But in my opinion, it wont hurt you at all. Just basing it on my own experiences.
Hope this helps.
One way to find out is to take them all together one morning and see what it does. I can tell you that it wont kill you !!