My girlfriend is on a high dose of codeine and also takes Fluoxetine (aka Prozac). She gives the following advice for her fellow stoners:
"Start small - have a wee toke to see how it sits. If you feel fine then you can smoke all you want.
Be a social smoker - if you do have a bad reaction (and it could happen after weeks of happy highs) it's best to have someone there to bring you down. I had a few problems when my pain was bad one time, I got paranoid and convinced I was dying. Turns out it was physical side effects of the prescription drugs and the weed related paranoia made it a million times worse. Over 2 days I had one trip to A & E and 2 ambulances called, at the worst point I was sure I was having a stroke (it was a panic attack). God knows what would have happened if I'd been alone at the time.
Use your common sense - no one can predict how you might react and only you will know when something's not right. I've smoked hundreds of spliffs with no problem and will continue to do so. If I feel a bit nauseas then I put the joint down until it passes - obvious really.
Oh, and I've not noticed anything different about the highs I've experienced since I've been on Prozac - sorry to burst your bubble

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