data + articles · 2 listed
newest 1989spec sheet8 rows
B-193 is an experimental beta-carboline compound studied in the late 1980s and 1990s as an atypical antidepressant with serotonin 5-HT2 receptor blocking activity. It was never marketed.
- Showed an atypical antidepressant-like profile in rodent studies
- Blocks serotonin 5-HT2 receptor activity without affecting reuptake
- Toxicity screening was limited to animal studies
Overview
An old Polish Academy of Sciences research compound; interesting because it blocked serotonin 5-HT2 receptors without touching reuptake, but it stayed a lab curiosity.
Mechanism
B-193 acts as an at 5-HT2 receptors and alpha1- receptors, with much lower affinity for 5-HT1 and alpha2-adrenergic receptors. Unlike classic tricyclic or antidepressants, it does not inhibit serotonin or reuptake. In animal studies it reversed the head-twitch response induced by 5-HTP and LSD (a marker of 5-HT2 receptor activity) and blocked hyperthermia caused by fenfluramine and mCPP, while leaving dopaminergic responses largely unaffected; it did enhance amphetamine-induced hyperlocomotion in one study.
receptor fingerprint
5-HT2 receptorAntagonist
Alpha1- receptorAntagonist
Safetyrisks and cautions, not medical advice
B-193 was evaluated for cumulative, subchronic, and chronic toxicity in animal studies through the mid-1990s, including assessment of embryotoxic effects in mice. It was never tested in humans, so no clinical safety or tolerability data exists.
Subjective profileweighing the evidence above
Never tested in a single human, so there is nothing here to recommend or to buy. It is a footnote from a 1990s attempt at a 5-HT2 blocking antidepressant, interesting only as pharmacology history.
Resources
This entry is here for reference.
Research
- 1.Antiserotonin activity of 9-methyl-2-[3-(4-phenyl-1-piperazinylpropyl)]-1,2,3,4-tetrahydro-beta-carbolin-1-one (B-193)
- 2.Antidepressant profile of 9-methyl-2[-3-(4-phenyl-1-piperazinylpropyl)]-1,2,3,4-tetrahydro-beta-carbolin-1-one (B-193)
2 listed here; entry last updated July 2026
Reviews
My notesprivate to this device
FAQ
What is B-193 used for?
Nothing today. It was a research compound studied in Polish Academy of Sciences labs in the late 1980s and 1990s as a possible atypical antidepressant, but it never reached human trials or the market.
How does B-193 work?
It blocks serotonin 5-HT2 receptors and, to a lesser degree, alpha1-adrenergic receptors, without inhibiting serotonin or norepinephrine reuptake the way older antidepressants do.
Is B-193 well-researched?
It has a handful of published animal pharmacology and toxicology papers from the late 1980s through the mid-1990s, but no human data and no modern research interest.
Limitations of the evidence
- Never tested in humans, so no clinical safety data exists
Adverse effects
- Toxicity screening was limited to animal studies
Notes and cautions
- Never marketed or approved anywhere