Tropisetron

Tropisetron, coded ICS 205-930 during development and marketed as Navoban, is a serotonin 5-HT3 receptor antagonist approved as an antiemetic in Japan and in many other countries outside the United States, with ATC code A04AA03 (KEGG DRUG D02041, D02130). It has never been approved by the FDA, which is why American research groups describe it as a drug already approved for clinical use outside the United States (PMID: 15927799). Material sold on the research chemical market as Tropiestron is a misspelling of the same drug.

Interest beyond nausea comes from a second property. Tropisetron is a partial agonist at the alpha7 nicotinic acetylcholine receptor. Oocyte electrophysiology traced that activity to the tropane portion of the molecule and showed that the indole portion mainly determines potency and subtype selectivity (PMID: 15781147). Positron emission tomography with the alpha7 radioligand CHIBA-1001 showed that a single oral dose lowered radioligand distribution volume in the human brain while ondansetron did not, so alpha7 engagement happens at ordinary clinical exposure (PMID: 23430308). A separate drug screen also found that it binds the ectodomain of amyloid precursor protein (PMID: 24389031).

Preclinical work follows that thread. Tropisetron improved deficient inhibitory processing of the auditory evoked potential in DBA/2 mice, an effect blocked by the alpha7 antagonist methyllycaconitine (PMID: 16136299); improved phencyclidine-induced cognitive deficits in mice, again blocked by methyllycaconitine (PMID: 17094961); and improved apomorphine-disrupted prepulse inhibition in Wistar rats (PMID: 20673759). In J20 transgenic mice it improved memory and the sAPPalpha to amyloid-beta ratio more than memantine or donepezil at comparable doses (PMID: 24389031). Outside the brain it reduced collagen synthesis in human dermal fibroblasts and reduced established dermal fibrosis in a bleomycin mouse model of scleroderma through alpha7 receptors (PMID: 23440693).

Human trials outside emesis are small but real. Three randomized controlled trials, each with 40 patients with schizophrenia stabilized on risperidone, reported improved P50 auditory gating and cognition after 10 days (PMID: 22952075), improved P50 gating and sustained visual attention after 8 weeks (PMID: 20573264), and improved negative symptoms after 8 weeks (PMID: 23515583). In fibromyalgia, a randomized double-blind placebo-controlled multicenter trial in 21 women reported a larger fall in pain scores than placebo, which reached significance on a secondary body diagram score and not on the primary visual analog scale (PMID: 15370724).

Pharmacokinetics are dominated by CYP2D6. In 18 healthy volunteers, oral bioavailability ranged from 0.27 to 0.99 and correlated inversely with CYP2D6 activity measured by the sparteine metabolic ratio, with a half-life near 5.7 h (PMID: 11736884). Poor metabolisers get higher exposure with more headache and constipation, ultrarapid metabolisers get less antiemetic effect, and this relationship is now covered by a Clinical Pharmacogenetics Implementation Consortium guideline for CYP2D6 genotype and 5-HT3 receptor antagonists (PMID: 8363993, PMID: 12065557, PMID: 41979467). Every use outside the licensed antiemetic indication is investigational.

Tropisetron is available in capsule form.

Compare prices, payment methods, shipping, and COA scores across 1 vendor.

1 of the vendors BodyHackGuide tracks list Tropisetron (1 listing). The lowest listed price BodyHackGuide has recorded for Tropisetron is $89.99. No Tropisetron listing recorded as in stock carries a milligram count, so BodyHackGuide states no price per milligram for Tropisetron.

BodyHackGuide holds 1 third-party certificate record for Tropisetron, from Disguised Alpha. No editor has read any of BodyHackGuide's 1 certificate record for Tropisetron. The laboratory named on BodyHackGuide's Tropisetron certificate record is Freedom Diagnostics Testing, and the test date on it is 30 July 2026. Each vendor page on BodyHackGuide shows how many certificate records BodyHackGuide holds for that vendor and links to each record that has its own page.