Thioproperazine (Majeptil): Why This Phenothiazine Is Not in U.S. Pharmacies and What Telehealth Can Still Do

Last updated: August 25, 2026

Thioproperazine is a first-generation phenothiazine sold in some countries as Majeptil (you may also see thioperazine, Mayeptil, Cephalin, or Vontil on old charts). Families type those names after a Canadian hospital list, a French or Brazilian label, or a 1960s ward order. It is not a current U.S. retail option. This guide explains what thioproperazine is, how DrugBank and identifier registries describe it, how it differs from thiopropazate (Dartal), and how telehealth can still help someone who needs an evaluation for psychosis, mania, or related symptoms.

This page is educational. It is not a diagnosis, a refill promise, or a claim that any plan will pay for a specific drug. Coverage varies by plan. Verify benefits before you book.

See conditions Klarity treats or start with online anxiety treatment if worry, restlessness, or tension is the main problem you want to discuss.

TL;DR

• DrugBank lists thioproperazine as DB01622 (brand Majeptil). The public summary describes an antipsychotic for acute and chronic schizophrenia, including cases that did not respond to more common neuroleptics, and for manic syndromes. That is a catalog indication, not a current U.S. label. (DrugBank DB01622)
• Public identifier records commonly list CAS 316-81-4, PubChem CID 9429, ChemSpider 9058, UNII YJ050AQ56X, KEGG D08585, ChEBI CHEBI:59120, ChEMBL CHEMBL609109, EPA CompTox DTXSID1023655, ECHA 100.005.695, ATC N05AB08, formula C22H30N4O2S2, about 446.63 g/mol. Treat those as catalog IDs, not a current prescription. (Wikipedia identifier table, verified against registry links)
• Do not confuse thioproperazine (Majeptil, DB01622) with thiopropazate (Dartal, DB13557). They are different piperazine phenothiazines. (DrugBank DB13557)
• Do not buy research-grade powder or unlabeled overseas tablets and swallow them. Phenothiazines as a class still carry LiverTox cautions, including cholestatic injury patterns best documented with chlorpromazine and reported, less often, with other phenothiazines. (LiverTox fluphenazine / phenothiazine class note)
• Medicare behavioral telehealth in the home remains available on a permanent basis, with several other Medicare telehealth flexibilities extended through December 31, 2027 (HHS page last updated February 5, 2026). Klarity’s 2,000+ licensed providers can evaluate current symptoms and discuss medicines that U.S. pharmacies still stock. (HHS Medicare telehealth payment policies)

On this page

• What is thioproperazine?
• Majeptil, identifiers, and why U.S. shelves are empty
• Thioproperazine is not thiopropazate (Dartal)
• Safety, class risks, and what not to do
• What telehealth can still do
• How Klarity fits
• FAQ

What is thioproperazine?

Thioproperazine is a typical (first-generation) antipsychotic in the phenothiazine family. The piperazine side chain and the dimethylsulfonamide group on the ring put it next to other potent piperazine phenothiazines, not next to more sedating aliphatic drugs such as chlorpromazine. DrugBank’s public card states it is indicated for acute and chronic schizophrenia, including cases refractory to more common neuroleptics, and that it may also be used for manic syndromes. That wording is a database summary. It is not a U.S. Prescribing Information sheet you can take to a chain pharmacy.

Secondary compound pages list historic uses as a tranquilizer, antiemetic, and sedative, and as treatment for schizophrenia and the manic phase of bipolar disorder. They also note Majeptil 10 mg tablets in some markets. Treat milligram figures from those pages as historic or foreign-label context, not as a current U.S. dose you can fill tomorrow. (Thioproperazine compound page)

Related Klarity first-generation guides include thiopropazate (Dartal), butaperazine (Repoise), carphenazine (Proketazine), and promazine (Sparine).

Klarity does not restart Majeptil. A licensed clinician can still review current symptoms and talk through medicines U.S. pharmacies actually stock.

Majeptil, identifiers, and why U.S. shelves are empty

Majeptil is the brand most often attached to thioproperazine. Older lists also use thioperazine, Mayeptil, Cephalin, and Vontil. A Health Canada consumer leaflet for thioproperazine mesylate tablets still exists as a PDF (dated October 25, 2022 on the public file). That is Canadian labeling history, not proof that a U.S. pharmacy can dispense the same product. (Health Canada thioproperazine mesylate Part III leaflet)

ATC code N05AB08 places thioproperazine with other piperazine phenothiazines. WHO’s ATC/DDD index still carries the code even when a product has left a national market. A code in a classification table is not a signal that a U.S. pharmacy can fill the drug tomorrow.

Useful identifiers when a records team traces an old order:

• DrugBank: DB01622
• UNII: YJ050AQ56X
• CAS: 316-81-4
• PubChem CID: 9429
• ChemSpider: 9058
• KEGG: D08585; ChEBI: CHEBI:59120; ChEMBL: CHEMBL609109
• EPA CompTox: DTXSID1023655
• ECHA InfoCard: 100.005.695
• ATC: N05AB08
• InChIKey: VZYCZNZBPPHOFY-UHFFFAOYSA-N
• IUPAC-style name in public registries: N,N-dimethyl-10-[3-(4-methylpiperazin-1-yl)propyl]-10H-phenothiazine-2-sulfonamide (registry wording varies slightly around the sulfonamide vs carboxamide line; use CAS/UNII to confirm the structure)
• Formula: C22H30N4O2S2 (~446.63 g/mol)

Treat every milligram figure you find in old monographs or foreign leaflets as historic. They are not a current U.S. label you can fill at a chain pharmacy.

Thioproperazine is not thiopropazate (Dartal)

The names look alike. The molecules do not. Thioproperazine is DrugBank DB01622 (Majeptil), CAS 316-81-4, ATC N05AB08. Thiopropazate is DrugBank DB13557 (Dartal), CAS 84-06-0, ATC N05AB05, and public chemistry sources describe it as a perphenazine prodrug. Mixing the two on a records request is a common error. If a chart says “Dartal,” read the thiopropazate guide. If it says “Majeptil,” you are in this article.

Safety, class risks, and what not to do

First-generation phenothiazines can cause extrapyramidal symptoms, tardive dyskinesia, sedation, anticholinergic effects, orthostasis, and, as a class, rare but documented cholestatic liver injury. LiverTox’s fluphenazine chapter states that all phenothiazine antipsychotic agents are probably capable of causing cholestatic liver injury, though frequency appears lower for some members than for chlorpromazine. (LiverTox NBK548610)

Secondary safety lists for thioproperazine also mention amenorrhea, sexual side effects, breast swelling and milk production, insomnia, constipation, low urine output, dizziness, dry mouth, nausea, headache, and weight change as common effects, and agranulocytosis, neuroleptic malignant syndrome, sudden cardiac death, and torsades de pointes as rare but serious ones. Elderly people with dementia-related psychosis who take antipsychotics have a higher risk of death than those who do not. Those statements come from compiled compound pages, not a current U.S. boxed-warning label for this specific brand. (Thioproperazine compound page)

None of that is a reason to mail-order unlabeled “Majeptil” powder. Research-chemical listings exist because the structure is old and catalogued. Those listings are not pharmacies. Swallowing an unregulated phenothiazine skips identity testing, dose control, and monitoring for movement disorders and liver injury.

If someone is in crisis, call or text 988 in the United States, or use local emergency services. Telehealth is for planned evaluation, not for an emergency.

What telehealth can still do

A licensed clinician can take a history of the old Majeptil exposure, current symptoms (psychosis, mania, severe anxiety, insomnia, agitation), other medicines, and medical risks. They can discuss current U.S. options in the same therapeutic neighborhood, including later antipsychotics that pharmacies still stock. They cannot lawfully restart a foreign or withdrawn brand just because a relative remembers the name.

HHS summarizes current Medicare telehealth rules on a page last updated February 5, 2026. Medicare patients can permanently receive behavioral and mental telehealth in the home, with no geographic originating-site restriction for those services. Recent legislation also extended many other Medicare telehealth flexibilities through December 31, 2027, including home originating sites for some non-behavioral care, audio-only options in defined cases, and a pause on the in-person visit that would otherwise be required within six months of an initial Medicare behavioral telehealth service. Commercial and Medicaid rules differ. Coverage varies. Verify benefits. (HHS Medicare payment policies)

How Klarity fits

Klarity is an online clinic with 2,000+ licensed providers. Visits focus on conditions the practice actually treats, including anxiety, depression, ADHD, insomnia, and related mental health care. A visit is an evaluation. It is not a guarantee of a controlled-substance prescription or of any specific historic drug.

If anxiety, restlessness, or tension is the presenting problem, start at online anxiety treatment. For a broader list of conditions, use Klarity’s condition pages.

Insurance may help pay for an eligible visit. Plans differ on telehealth, prior authorization, and pharmacy benefits. Ask your plan, then confirm with the care team.

FAQ

Is Majeptil still available in the United States?

No current U.S. retail product is in routine use under the Majeptil name. DrugBank still carries a public card (DB01622). Some other countries have used the brand. Treat any leftover bottle as a historic or imported artifact and ask a clinician before you assume it is still safe or authentic.

Is thioproperazine the same as thiopropazate (Dartal)?

No. Thioproperazine is DB01622 (Majeptil). Thiopropazate is DB13557 (Dartal). Mixing the two names is a common records error.

Can a Klarity visit prescribe Majeptil?

No. A visit can review current symptoms and discuss medicines U.S. pharmacies stock. It cannot recreate a foreign or withdrawn phenothiazine brand.

Will insurance cover a telehealth visit about an old antipsychotic?

Maybe. Coverage varies by plan, state, and whether the visit is billed as an eligible evaluation. Verify benefits before you book. This is not a claim that any insurer covers Majeptil or any specific medicine.

If you or someone near you is in immediate danger, call 988 or emergency services now.