Salvinorin A is the substance in Salvia divinorum leaves that causes the plant's effects. It acts on the kappa opioid receptor, a target that none of the classic psychedelics use, and it is active in amounts of a few hundred micrograms. Both facts explain why salvia feels unlike psilocybin, LSD or mescaline, and why its effects are so short.
Class. Neoclerodane diterpene. Unlike most plant psychoactives it contains no nitrogen, so it is not an alkaloid.
A potent substance from a leaf
Salvinorin A is found mainly in the leaves and, in smaller amounts, in the stems (DEA Diversion Control, 2025). Pure salvinorin A taken in doses of 200 to 500 micrograms (0.2 to 0.5 mg) produces effects that early experimenters found identical to those of the whole herb (Siebert, 1994). By weight that made it the most potent naturally occurring hallucinogen isolated at the time (Valdés, 1994).
A dried leaf contains a few milligrams of salvinorin A per gram. Laboratory measurements of leaf products range from about 1.5 to 5 mg per gram (Chambers et al., 2022; Tsujikawa et al., 2008). One gram of leaf therefore holds several times the active amount, which is why extracts and careful measuring matter so much. See leaves and extracts.
Scale. 1 mg = 1,000 µg. The active range of 200 to 500 µg is 0.0002 to 0.0005 gram.
The kappa opioid receptor
In 2002 a research team screened salvinorin A against dozens of receptors in the brain. It bound strongly and selectively to one: the kappa opioid receptor. It had no significant activity at 50 other receptors, transporters and ion channels they tested, and none at the serotonin 5-HT2A receptor (Roth et al., 2002).
That last point is the main difference with classic psychedelics. Psilocybin, LSD and mescaline produce their effects mainly through 5-HT2A. Salvinorin A does not touch it.
"Opioid" in this context does not mean it acts like morphine or heroin. Those act mostly on the mu opioid receptor. In laboratory tests salvinorin A was a full agonist at the kappa receptor and showed no activity at the mu or delta receptors (Wang et al., 2005). In mice bred without kappa receptors its effects disappeared (Ansonoff et al., 2006).
Agonist. A substance that activates a receptor. An antagonist blocks it.
Confirmed in people
A placebo-controlled study in Barcelona gave 24 healthy volunteers with psychedelic experience 1 mg of vaporised salvinorin A, sometimes after a blocking drug. Naltrexone, which blocks opioid receptors, prevented the effects. Ketanserin, which blocks 5-HT2A, did not (Maqueda et al., 2016). The same study measured peak blood levels one to two minutes after inhaling, a rise in systolic blood pressure and a release of the hormones cortisol and prolactin.
How it differs from classic psychedelics
| Feature | Salvinorin A (inhaled) | Psilocybin, LSD, mescaline |
|---|---|---|
| Main target | Kappa opioid receptor | Serotonin 5-HT2A receptor |
| Chemistry | Diterpene, no nitrogen | Alkaloids (contain nitrogen) |
| Active amount | 0.2 to 0.5 mg | Milligrams or more |
| Peak | About 2 minutes | After one hour or more |
| Typical duration | 15 to 20 minutes | Several hours |
| Character | Strong dissociation, loss of contact with surroundings, memory gaps | Changes in perception and thought, usually with awareness of surroundings |
Sources for the salvinorin A column: Johnson et al., 2011; MacLean et al., 2013; González et al., 2006. Human studies found some overlap with classic psychedelics on standard questionnaires, but participants also scored high on dissociation and had trouble remembering what happened. Many said the effect was qualitatively different from any other drug (MacLean et al., 2013).
Why swallowing does not work
Salvinorin A is broken down in the stomach and gut, so swallowed leaves or capsules have little effect (Siebert, 1994). In blood plasma, enzymes called carboxylesterases convert it into salvinorin B and other products, at least in rat plasma studied in the laboratory (Tsujikawa et al., 2009). Salvinorin B is inactive (Ansonoff et al., 2006). This fast breakdown is one reason the effect ends so quickly.
The route through the mouth lining is less reliable than it sounds. In a placebo-controlled trial, pure salvinorin A dissolved in a solvent and held under the tongue at doses up to 4 mg produced no effect that differed from placebo (Mendelson et al., 2011). Chewing fresh or moistened leaves, the traditional method, does work, but how much of the salvinorin A gets absorbed this way has not been measured well.
What this means in practice
- The active amount is tiny, so small weighing errors with extracts make large differences.
- The effect builds within seconds when inhaled. There is no time to change your mind after the first breath.
- Because it works differently, experience with psilocybin or LSD does not predict how salvia will feel.
Read on: effects and duration, safety and the sitter.