4-PrO-MET is a synthetic tryptamine and a prodrug of 4-HO-MET: the body converts it into 4-HO-MET after intake. Every Psilo Drops product is available in a 4-PrO-MET version. This page explains what 4-PrO-MET is, how it works, how it differs from 4-HO-MET, what is known about dose and duration, and where it stands legally.
What is 4-PrO-MET?
4-PrO-MET stands for 4-propionyloxy-N-methyl-N-ethyltryptamine, also written as O-propionyl-4-HO-MET. It is the propionate ester of 4-HO-MET, in the same way that 4-AcO-MET is the acetate ester. The molecule belongs to the synthetic tryptamines and is a structural relative of 4-PrO-DMT, the propionate ester of psilocin.
4-PrO-MET is a very recent compound. It first appeared on the market in the second half of 2025. There is almost no scientific literature on the substance itself; what is known comes from the chemistry of related esters, from binding data on 4-PrO-DMT published by CaaMTech, and from anecdotal reports.
How does 4-PrO-MET work?
4-PrO-MET is a prodrug. After oral intake, esterase enzymes in the body cleave off the propionyl group, leaving 4-HO-MET, the pharmacologically active molecule. The effects of 4-PrO-MET are therefore attributed to 4-HO-MET, in the same way that psilocybin is converted into psilocin and 4-AcO-DMT into psilocin.
Because the conversion takes time, anecdotal reports describe a slightly later and more gradual onset than with 4-HO-MET itself, and a longer total duration. The character of the experience is described as the same: visual, mentally clear and relatively light. Read more about the active molecule on our 4-HO-MET page.
Does it contain psilocybin or mushrooms?
No. Psilo Drops contain no mushrooms, no psilocybin and no psilocin. 4-PrO-MET is a lab-made ester that converts into 4-HO-MET, a synthetic relative of psilocin. People often search for these products as magic mushroom drops or psychedelic drops, and we use that name too, but the contents are a single, lab-tested synthetic compound with a fixed amount per drop.
4-PrO-MET versus 4-HO-MET
| Aspect | 4-HO-MET | 4-PrO-MET |
|---|---|---|
| Mechanism | Directly active | Converted into 4-HO-MET in the body |
| Onset (anecdotal) | 15 to 40 minutes | Somewhat later, more gradual |
| Total duration (anecdotal) | 4 to 6 hours | 6 to 8 hours |
| Character | Visual, clear, relatively light | The same, via the same active molecule |
| On the market since | About 2010 | 2025 |
| Published data | Limited | Very limited, mostly anecdotal |
We do not present 4-PrO-MET as safer, milder or more natural than 4-HO-MET. It is a synthetic ester, and because it becomes 4-HO-MET in the body, the same risks and contra-indications apply. The practical differences are the longer timeline and the legal status in some countries.
Dose and duration
There are no clinical studies on 4-PrO-MET. Anecdotal sources describe an oral range of about 15 to 20 mg as comparable to the common 4-HO-MET range, with a peak 1 to 3 hours after intake and a total duration of about 6 to 8 hours. Individual sensitivity varies a great deal, and because the compound is so new, reports are fewer and less consistent than for 4-HO-MET.
The Psilo Drops 4-PrO-MET versions carry the same amount per drop as the 4-HO-MET versions, so the drop counts in our dosing guide apply as a starting point. Reports consistently advise starting low and allowing the full, longer timeline before judging the effect.
Is 4-PrO-MET legal?
The Netherlands: 4-PrO-MET is not listed on List I, List II or List IA of the Dutch Opium Act. The substance-group ban of 1 July 2025 covers phenethylamines, synthetic cannabinoids and 4-aminopiperidines, not tryptamines. The product falls under the Commodities Act and NVWA supervision, which is why we sell it for research purposes and make no health claims.
Belgium: tryptamines are banned as a group since 2017. 4-PrO-MET is illegal there and we do not ship to Belgium.
Other EU countries: several countries that control 4-HO-MET do not control 4-PrO-MET, which is why the 4-PrO-MET version exists. There is no harmonised EU rule and legislation changes quickly. Our checkout only accepts countries where we can ship, and it is your responsibility to check the rules in your country before ordering.
Safety and contra-indications
Because 4-PrO-MET becomes 4-HO-MET in the body, the known risks of 4-HO-MET apply: at high doses, psychotic symptoms, a raised heart rate and blood pressure, and overheating. On top of that comes the uncertainty of a compound with almost no human data, including possible interactions that are not yet documented.
Do not use Psilo Drops if you are under 18, pregnant or breastfeeding, have a history of psychosis, schizophrenia or bipolar disorder, have a cardiovascular condition, or take SSRIs, SNRIs, MAOIs or lithium. Do not combine with alcohol or other drugs. Plan for the longer timeline: do not drive or operate machinery that day. Store cool and dark, out of reach of children and animals.
Psilo Drops with 4-PrO-MET
Choose the 4-PrO-MET version on the product page. All three products are lab-tested and dissolved so that every drop carries a fixed amount; they differ only in concentration.
- Psilo Drops Classic: about 3 mg per drop. The original. 2 ml, 5 ml and 10 ml.
- Psilo Light: about half the concentration of Classic. For a first or milder experience. 5 ml and 10 ml.
- Psilo Micro: about a tenth of the concentration of Classic. Developed for microdosing. 15 ml.
Frequently asked questions
Disclaimer: this product is intended for research purposes only and is not for human consumption. For persons aged 18 and over. Keep out of reach of children and animals. This product is not a medicine and is not intended to diagnose, treat, cure or prevent any disease. Sources: PsychonautWiki; CaaMTech binding data on 4-PrO-DMT; Shulgin, TiHKAL entry 21 (4-HO-MET); Dutch Opium Act lists as of May 2026.