Thiobuscaline
Overview
Thiobuscaline (TB), or 4-thiobuscaline (4-TB), also known as 3,5-dimethoxy-4-butylthiophenethylamine, is a psychoactive drug of the phenethylamine and scaline families related to the psychedelic drug mescaline. It is the analogue of buscaline in which the butoxy group at the 4 position has been replaced with a butylthio group. The drug is a non-hallucinogenic serotonin 5-HT2A receptor agonist with similar effects and potential uses to those of Ariadne.[1–4] WP
Drug class
Non-hallucinogenic serotonin 5-HT2A and 5-HT2C receptor agonist Psychoactive drug Antidepressant WP
From the Wikipedia article's infobox.
Uses, dosage and effects
Use and effects
In his book PiHKAL (Phenethylamines I Have Known And Loved) and other publications, Alexander Shulgin lists thiobuscaline's dose range as 60 to 120 mg orally and its duration as about 8 hours. Its onset is about 1 hour. The effects of thiobuscaline have been reported to include a "benign and beautiful experience which never quite popped into anything psychedelic", subtle threshold effects, a vague awareness of something, being in a "wonderful place spiritually" but with "some dark edges", it being "pleasant, but certainly not psychedelic", and body discomfort. No clear hallucinogenic effects were described. Thiobuscaline is listed as being 4 times more potent as a psychoactive drug than mescaline.[1]
Thiobuscaline produced perpetual threshold psychoactive effects that did not further increase across a wide dose range of 35 to 120 mg orally. Shulgin described it as "always the simple and ephemeral catalyst of euphoria without substance and without body". In addition, he said that it could not easily be classified, for instance as a psychedelic or stimulant. Instead, Shulgin likened thiobuscaline to Ariadne (4C-D), which he noted had been called an "antidepressant". He hypothesized that thiobuscaline might be beneficial for treatment of depression in certain people in the exact same way as Ariadne.[1] WP
Pharmacology
Pharmacodynamics
Thiobuscaline shows affinity for the serotonin 5-HT2A receptor (Kᵢ = 602 nM). It is a potent near-full agonist of the serotonin 5-HT2A and 5-HT2C receptors and to a much lesser extent a moderate-efficacy partial agonist of the serotonin 5-HT2B receptor, with EC₅₀ (half-maximal effective concentration) (Eₘₐₓ (maximal efficacy)) values of 3.86 nM (114%) at the serotonin 5-HT2A receptor, 89.6 nM (55.7%) at the serotonin 5-HT2B receptor, and 8.86 nM (95.9%) at the serotonin 5-HT2C receptor. Conversely, it was inactive as an agonist of the serotonin 5-HT1A receptor. The drug produces the head-twitch response, a behavioral proxy of psychedelic effects, in rodents.[4] WP
Pharmacokinetics
The in-vitro metabolism of thiobuscaline has been studied.[4] WP⚠ A word may be missing here. It reads this way in the source too.
History
History
Thiobuscaline was first described in the scientific literature by Alexander Shulgin and Peyton Jacob III in 1984. Subsequently, it was described in greater detail by Shulgin in his book PiHKAL (Phenethylamines I Have Known and Loved) in 1991.[1]
Legal status
Canada
Thiobuscaline is not a controlled substance in Canada as of 2025.[6] WP
United states
Thiobuscaline is not an explicitly controlled substance in the United States. However, it could be considered a controlled substance under the Federal Analogue Act if intended for human consumption.[7] WP
Chemistry
Harm reduction information
No harm reduction data is on file for this compound yet. That means no dose, timing or combination data from PsychonautWiki or TripSit. Please don't guess a dose from similar compounds. If you have taken it and feel unwell, contact emergency services or a poison control center.
Shulgin notes
These figures come from the Shulgins' own small trials, published decades ago. They are history, not a dosing guide: they were never checked the way a harm reduction dose table is, and batches, purity and people differ.
In Shulgin's words
Wikipedia's article on this compound, quoting Shulgin.
Instead, Shulgin likened thiobuscaline to Ariadne (4C-D), which he noted had been called an "antidepressant". WP
Read entry #149 in Erowid's online library
From PiHKAL and TiHKAL by Alexander and Ann Shulgin, as tabulated in Wikipedia's articles on the books (CC BY-SA 4.0). The books' text belongs to the Shulgins, so only the listed figures and a link are given here. Synthesis details are never shown on this site.
User reports
Erowid erowid.org
ListingsBluelight bluelight.org
ListingsReddit reddit.com
ListingsPop culture
No references added yet.
Add a reference
Registered users can add songs, films, books, shows, games and art about this substance. Link a source that names the substance, such as the work's Wikipedia article, a review or an interview, not only the work itself. Entries are voted on and moderated like every other value on this page.
Opens when accounts launch.
Sources
- Harm reduction site CitePiHKAL
- Journal / agency Jacob P, Shulgin AT. Hallucinogens: An Update. 1994. PMID 8742795
- Other Shulgin AT. Hallucinogens: A Forensic Drug Handbook. 2003
- Other Phenalkylamines and methods of making and using the same. 14 March 2022
- Journal / agency Jacob P, Shulgin AT. Sulfur analogues of psychotomimetic agents. 3. Ethyl homologues of mescaline and their monothio analogues. J Med Chem. July 1984. doi:10.1021/jm00373a013 · PMID 6737431
- Other Controlled Drugs and Substances Act
- Other Orange Book: List of Controlled Substances and Regulated Chemicals (January 2026). January 2026
Text and values on this page are quoted from Wikipedia (CC BY-SA 4.0), PubChem (public domain). Each value links to the exact revision it came from.