AJ replied: "You need at least 4-6 weeks before you do this. In majority of cases, SSRIs reduce the effects of Serotonergic psychedelics like LSD. However in some people, SSRIs can enhance the activity of hallucinogens like LSA. There are a few studies done on this. If you are still going to do it, I'd recommend that you give yourself a minimum of 6 weeks. There have been a lot of misconceptions that taking LSD with an SSRI can cause severe psychiatric disturbances. Not true. LSD can cause that all by itself. But the combination of SSRIs+LSD does not enhance depression or cause agitation, suicidal ideation or brain damage or rubbish like that. Now this varies from individual to individual but in general: SSRIs: decrease the effects of LSD Tricyclic anti-deps: increase the effects of LSD MAOIs: very dangerous to combine with LSD With Sertraline in particular, 50mg/day doses have had no effect on LSD but 100mg/day there will be a decrease in the effects of LSD. One last thing. Taking LSD after you have been on SSRIs can increase the occurence of "flashbacks". Hope this is helpful. EDIT: To the last poster, listen, my role here is NOT to act as a nanny. People are going to do drugs regardless of what you say. So the least you can do is to give them enough information so they won't KILL themselves. That is my goal. In NO WAY have I ever advocated recreational drug use. So don't tell me what a Pharmacologist should do. I have been in this field for many years and I'm an Addiction specialist. People will do what they want. Rather that giving them unhelpful comments which they are not going to listen, at least provide them with info so that they can make up their own minds and take responsibility for their own actions. It is not our role or right to play Nanny! Again, don't tell me how a pharmacologist should act. Do you even know the tiniest bit about the research we do? We are NOT the moral police. And this is Yahoo Answers, not Yahoo Opinions. I really don't care how many times you thumbs-down me because it's meaningless to me as are points. I only care about providing accurate info, not giving moral lectures! As for Serotonin Syndrome, do you even know the first thing about it? Because if you did, you would not be coming up with RUBBISH like that. It does NOT happen this way. If you presented logical arguments, I could accept it. But everything you have given is YOUR opinion and NOT backed up by science. If you want to post something like this, DO YOUR RESEARCH FIRST! Do you really think I would post an answer that did not check for drug-drug interactions? How irresponsible do you think I am? Every single one of my answers pertaining to drugs, has been about providing information. And that is exactly what I have done. So the next time you want to argue drug interactions with me, DO YOUR RESEARCH FIRST! We (my colleagues and me) have specialized in this field for the past decades! All this talk about agitation and depression because of SSRIs+LSD, is utter RUBBISH. As I said, if you suffer from pre-existing conditions, then you should obviously not take LSD. But combining it with SSRIs do NOT induce this sorta thing! Again, you claim to be a pharmacologist as well,,,,,,so do your resaerch properly. It absolutely riles me to see inaccurate gibberish posted! You may have met people who have had bad reactions to LSD. This is in most cases due to: 1) Overuse/abuse of LSD 2) Not everyone can take psychedelics due to pre-existing psychiatric conditions/illness Go to PubMed and read the many studies there on this topic. Then come back and tell me about interactions and tell me if ANYTHING I said was scientifically innaccurate. I never mentioned about Serotonin Syndrome because it DOES NOT HAPPEN! You are talking about combining Re-uptake inhibitors and 5HT-2a and -2c Agonists, not 2 SSRIs. LSD does not bind to the reuptake sites. Please, for God's sake do your research before spewing drivel like this. And if you claim you have done research and it does indeed cause Serotonin Syndrome, me and my colleagues would just love to read your research and comment on/peer review it we will you can be sure of it."