4-ACO-DMT (4-acetoxy-n,n-dimethyltryptamine), or O-Acetylpsilocin, is a psychedelic drug (hallucinogenic) in the tryptamine class of drugs (like LSD and psilocybin). It is the acetylated form of the psychedelic mushroom alkaloid psilocin (4-HO-DMT). It is a more stable compound than psilocin, and has a longer shelf life. It is commonly called "psilacetin" among its users. It is usually found in crystalline/powder form, in either it's fumarate or HCl salt. The dosage varies between 10 and 25mg. 25mg is approximately equal to 4 grams of good psychedelic mushrooms (17mg of psilocin, there is approx. 15mg of psilocin in a good 1/8th ounce of mushrooms). The effects are VERY similar to a mushroom trip, except it lasts a little longer than mushrooms (around 7 hours). Its effects, however, differ somewhat from mushrooms. It seems to have a much more relaxing quality to it, which makes it harder to have a bad trip. Several available reports of 4-ACO-DMT compare it favorably to psilocybin, describing it as more euphoric, gentle, warm, and colorful. It has also been described as less jarring/scary, and less likely to produce nausea. I and everyone I have talked to who has tried it loves it (most more than mushrooms). Users report dose-dependent colorful visual effects and a sense of physical energy or euphoria, sometimes accompanied by abstract, associative, "trippy" thought patterns, or derealization. It is almost always taken orally, but can be taken by other methods. It is not specifically illegal or scheduled in the USA, but it may be considered an analogue of psilocybin/psilocin, the illegal chemical in psychedelic mushrooms, because up to 90% of the chemical hydroxylizes into psilocin in your brain after ingestion.

As of 2007, it is a novel compound with relatively little availability. It is usually ordered from the internet through various research chemical distributors for between $130 and $200 per gram.

It is truly an awesome compound. It doesn't have a "research chemical" like body load, or even an unpleasant come-up. It can be truly and deeply psychedelic and visionary, just as much as more mainstream psychedelics like LSD, DMT, psilocybin, and mescaline can be. If you like mushrooms, you'll love this one. It's a gem indeed.
1: I just took 25mg of 4-ACO-DMT, also called psilacetin.
2: Really? So you're going to be tripping, similar to mushrooms, right? For how long?
1: Yes, are you available to be my sober sitter for the next few hours? I feel it starting to kick in.... It will last between 4-7 hours. You can try some of it in a few days, and I will trip sit you.
2: Awesome!
by psilocybonaut January 25, 2008
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