Acetophenazine (Tindal): Why This Phenothiazine Left U.S. Pharmacies and What Telehealth Can Still Do

Last updated: August 24, 2026

Acetophenazine is a moderate-potency phenothiazine antipsychotic. U.S. pharmacies sold it as Tindal (acetophenazine maleate). Clinicians used it for disorganized thinking, hallucinations, and other psychotic symptoms. It is not a current U.S. retail product. NCATS Inxight Drugs lists acetophenazine maleate as previously marketed, with first approval in 1961. A licensed telehealth clinician can still evaluate psychosis, anxiety, and related mood symptoms and discuss medicines that U.S. pharmacies actually stock. This page is education. It is not a prescription and it is not a promise that any clinician will start or restart acetophenazine.

This guide is educational. It is not a diagnosis.

Looking for mental health care online? Klarity Health has 2,000+ licensed providers. Many visits happen by video. Coverage varies by plan. Self-pay is also an option. See online anxiety treatment options or browse conditions.

TLDR

• Acetophenazine is a moderate-potency phenothiazine. DrugBank DB01063 lists it for disorganized and psychotic thinking and for false perceptions such as hallucinations or delusions. It primarily targets the dopamine D2 receptor.
• NCATS Inxight Drugs (UNII 3P5HNU5JTC): acetophenazine maleate; brand Tindal; originator Schering; first approved 1961; status US Previously Marketed. Sample oral use guide on that record: start 20 mg daily; usual 20 to 40 mg daily in a healthy young adult; increase by 20 mg as needed; maximum 60 mg in 24 hours.
• DrugBank mechanism: blocks postsynaptic mesolimbic dopaminergic D1 and D2 receptors; also depresses hypothalamic and hypophyseal hormone release and the reticular activating system. NCATS lists D2 antagonism (IC50 17.0 nM), sigma-opioid antagonism (Ki 36.0 nM), and modest androgen-receptor binding (Ki 0.8 µM). Unbound fraction 10% after a 20 mg single oral dose.
• A 2006 patent application (US20060039869A1) tabulated historic Tindal dosing as 20 mg tablet strength and 20 to 60 mg per day. That table is a historic reference, not a live U.S. label.
• No current DailyMed monograph for acetophenazine exists. Phenothiazines as a class still carry the boxed dementia-related mortality warning that appears on remaining first-generation products such as chlorpromazine and fluphenazine.
• LiverTox (NBK548793) documents cholestatic liver injury for chlorpromazine, the prototype phenothiazine. Treat acetophenazine as the same chemical family for liver caution.
• Not a controlled substance historically. Telehealth can review psychosis history and discuss available antipsychotics. A U.S. clinician cannot fill Tindal from a community pharmacy. Fever with stiff muscles, chest pain, fainting, or suspected overdose need emergency care. If you are in crisis, call or text 988.

Table of contents

• What acetophenazine is
• How it works
• Historic uses
• Historic dosing
• Side effects and class risks
• Warnings
• When telehealth is enough
• How a Klarity visit fits
• FAQ

What acetophenazine is

Acetophenazine is a piperazine phenothiazine. DrugBank classifies it as a small molecule in the approved group and lists synonyms acetophenazina and acetophenazinum. Average molecular weight is 411.56 (free base, C23H29N3O2S). The marketed salt was acetophenazine maleate (dimaleate), UNII 3P5HNU5JTC, molecular weight 643.705.

NCATS marks the product as previously marketed in the United States, first approved in 1961, originator Schering, brand Tindal, condition psychosis. Orange Book naming on that record is acetophenazine maleate. You will not find a current U.S. brand or generic on pharmacy shelves. Related Klarity first-generation guides: promazine (Sparine), mesoridazine (Serentil), prochlorperazine, and haloperidol (Haldol).

How it works

DrugBank says acetophenazine blocks postsynaptic mesolimbic dopaminergic D1 and D2 receptors. That blockade also depresses release of hypothalamic and hypophyseal hormones and is believed to depress the reticular activating system, which can change basal metabolism, body temperature, wakefulness, vasomotor tone, and emesis.

NCATS potency figures: dopamine D2 antagonist IC50 17.0 nM; sigma opioid receptor antagonist Ki 36.0 nM; androgen receptor antagonist Ki 0.8 µM, with a note of modest antiandrogen activity. Funbound is listed as 10% after a 20 mg single oral dose in humans. Absorption, half-life, and clearance fields on the public DrugBank card are not populated.

Historic uses

DrugBank indication: treatment of disorganized and psychotic thinking, plus help for false perceptions such as hallucinations or delusions. Pharmacodynamics text on the same card: intended for the management of schizophrenia and other psychotic disorders. NCATS lists psychosis as the approved condition and Tindal as the product name.

A Wiley review of phenothiazine antipsychotics (October 14, 2025) notes approval as a drug in 1961, former brand Tindal, and moderate potency. That is a chemistry review, not a prescribing label. Acetophenazine is not FDA-approved today for dementia-related psychosis, bipolar maintenance, or anxiety as a first-line home medicine.

Your clinician matches any current antipsychotic to your history. This article is education, not a personal prescription plan.

Want care that is actually available in 2026? Browse Klarity condition pages or see online anxiety treatment options. Coverage varies by plan. Verify benefits before you book.

Historic dosing

There is no live FDA label to quote. Two historic sources give overlapping oral ranges:

• NCATS sample in-vivo use guide: normal dosage 20 mg to 40 mg daily in a healthy young adult; start 20 mg daily; increases 20 mg as needed; keep maintenance as low as possible in 24 hours; maximum 60 mg in 24 hours; route oral.
• US20060039869A1 dosing table: acetophenazine (Tindal) 20 mg strength, 20 to 60 mg, once every 24 hours. That filing is a patent application, not FDA labeling.

Do not use those numbers to self-dose leftover tablets from another country. A U.S. clinician who sees you by video will talk about medicines they can actually prescribe and monitor.

Side effects and class risks

Public DrugBank and NCATS cards do not publish a complete adverse-event table for acetophenazine. Phenothiazine class effects still apply. On remaining labels (chlorpromazine, fluphenazine, perphenazine), those include drowsiness, dizziness, dry mouth, constipation, blurred vision, orthostatic blood-pressure drops, extrapyramidal symptoms, tardive dyskinesia, neuroleptic malignant syndrome, blood dyscrasias, photosensitivity, and heat intolerance.

LiverTox’s chlorpromazine chapter (updated October 5, 2017) is the best public liver reference for this chemical family. It reports liver-test abnormalities in up to 40% of people on long-term chlorpromazine, usually mild and self-limited, plus a well-known cholestatic injury pattern. Treat unexplained jaundice, dark urine, or right-upper-quadrant pain as a reason to stop a phenothiazine and get labs, even if the specific drug is historic.

Warnings

Older adults with dementia-related psychosis treated with antipsychotics have a higher risk of death. That boxed warning is on every remaining first-generation antipsychotic label. Acetophenazine is not approved for dementia-related psychosis.

Class contraindications on related phenothiazine labels typically include coma or severe CNS depression, blood dyscrasias, significant liver damage, and hypersensitivity to phenothiazines. Mesoridazine (Serentil) left the U.S. market in part because of QT prolongation. Acetophenazine does not have a published QT study of that size, but any phenothiazine plus other QT-prolonging drugs deserves a cautious clinician review.

Insurance coverage for a replacement antipsychotic may vary by plan. Patients should verify benefits before booking. Klarity does not promise that any plan will cover a specific medicine.

When telehealth is enough

Telehealth.HHS.gov policy updates (last updated February 5, 2026) state that Medicare patients can permanently receive behavioral and mental health telehealth in the home, with no geographic originating-site restriction, and that audio-only is permanently allowed for those Medicare behavioral services. An in-person visit within six months of an initial Medicare behavioral telehealth service is not required through December 31, 2027.

What video care can do: take a full history, review past antipsychotics, screen for EPS and tardive movements on camera, discuss metabolic labs, and prescribe a currently marketed oral antipsychotic when appropriate. What video care cannot do: dispense Tindal, give depot injections, or treat NMS, acute dystonia with airway risk, or suspected overdose. Those need a clinic or emergency department.

How a Klarity visit fits

Klarity Health has 2,000+ licensed providers. Many mental health visits happen by video. A clinician can talk through psychosis, anxiety, depression, and sleep, then offer options that U.S. pharmacies stock. Coverage varies by plan. Self-pay is also an option. Check if your plan may cover a visit. Verify benefits before you book.

See online anxiety treatment options →

Browse condition pages →

FAQ

Is acetophenazine still available in the United States?

NCATS lists acetophenazine maleate as previously marketed. There is no current DailyMed label. U.S. community pharmacies do not stock Tindal.

What was Tindal?

Tindal was the Schering brand of acetophenazine maleate, first approved in 1961, used for psychosis.

Is acetophenazine a controlled substance?

Historic records do not assign a DEA schedule. It was a prescription phenothiazine, not a stimulant or benzodiazepine.

Can a telehealth clinician prescribe acetophenazine?

A U.S. clinician cannot fill a product that is not on the market. They can evaluate symptoms and discuss available antipsychotics.

What should I do if I still have old Tindal tablets?

Do not take expired or foreign leftover antipsychotics without a clinician. Bring the bottle to a pharmacist for disposal guidance and book a visit to review a current plan.

Educational only. Not medical advice. Coverage varies by plan. Verify benefits before booking. If you are in crisis, call or text 988.