Last reviewed 2026-04-20 · How we verify

Homatropin (homatropine)

Homatropin (generic name: homatropine) is a Cholinergic Muscarinic Antagonist drug. It is currently FDA-approved for Constipation, Cough, Cycloplegia.

Homatropine is a small molecule cholinergic muscarinic antagonist that targets the muscarinic acetylcholine receptor M4. It is used to treat a variety of conditions, including constipation, cough, and peptic ulcers. Homatropine is off-patent and has a single generic manufacturer. As a muscarinic antagonist, it works by blocking the action of acetylcholine at muscarinic receptors, leading to decreased smooth muscle contraction and secretory activity. It is not FDA-approved for any indications.

At a glance

Approved indications

• Constipation
• Cough
• Cycloplegia
• Disorder of biliary tract
• Incomplete passage of stool
• Irritable bowel syndrome
• Peptic ulcer
• Perioperative Mydriasis
• Uveitis

Boxed warnings

• WARNING: ADDICTION, ABUSE, AND MISUSE; LIFE-THREATENING RESPIRATORY DEPRESSION; ACCIDENTAL INGESTION; MEDICATION ERRORS; CYTOCHROME P450 3A4 INTERACTION; CONCOMITANT USE WITH BENZODIAZEPINES OR OTHER CNS DEPRESSANTS; INTERACTION WITH ALCOHOL; NEONATAL OPIOID WITHDRAWAL SYNDROME Addiction, Abuse, and Misuse Hydrocodone bitartrate and homatropine methylbromide exposes patients and other users to the risks of opioid addiction, abuse, and misuse, which can l ead to overdose and death. Reserve hydrocodone bitartrate and homatropine methylbromide for use in adult patients for whom the benefits of cough suppression are expected to outweigh the risks, and in whom an adequate assessment of the etiology of the cough has been made. Assess each patient’s risk prior to prescribing hydrocodone bitartrate and homatropine methylbromide, prescribe hydrocodone bitartrate and homatropine methylbromide for the shortest duration that is consistent with individual patient treatment goals, monitor all patients regularly for the development of addition or abuse, and refill only after reevaluation of the need for continued treatment [see Warnings and Precautions (5.1)] . Life-Threatening Respiratory Depression Serious, life-threatening, or fatal respiratory depression may occur with use of hydrocodone bitartrate and homatropine methylbromide. Monitor for respiratory depression, especially during initiation of hydrocodone bitartrate and homatropine methylbromide therapy or when used in patients at higher risk [see Warnings and Precautions (5.2)] . Accidental Ingestion Accidental ingestion of even one dose of hydrocodone bitartrate and homatropine methylbromide, especially by children, can result in a fatal overdose of hydrocodone [see Warnings and Precautions (5.2)] . Risk of Medication Errors Ensure accuracy when prescribing, dispensing, and administering hydrocodone bitartrate and homatropine methylbromide. Dosing errors can result in accidental overdose and death. Always use an accurate milliliter measuring device when measuring and administering hydrocodone bitartrate and homatropine methylbromide [see Dosage and Administration (2.1), Warnings and Precautions (5.5)] . Cytochrome P450 3A4 Interaction The concomitant use of hydrocodone bitartrate and homatropine methylbromide with all cytochrome P450 3A4 inhibitors may result in an increase in hydrocodone plasma concentrations, which could increase or prolong adverse drug effects and may cause potentially fatal respiratory depression. In addition, discontinuation of a concomitantly used cytochrome P450 3A4 inducer may result in an increase in hydrocodone plasma concentration. Avoid the use of hydrocodone bitartrate and homatropine methylbromide in patients taking a CYP3A4 inhibitor or inducer [see Warnings and Precautions (5.7), Drug Interactions (7.2, 7.3)] . Risks From Concomitant Use With Benzodiazepines or Other CNS Depressants Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Avoid the use of hydrocodone bitartrate and homatropine methylbromide in patients taking benzodiazepines, other CNS depressants, or alcohol [see Warning and Precautions (5.8), Drug Interactions (7.5)] Interaction with Alcohol Instruct patients not to consume alcoholic beverages or use prescription or non-prescription products that contain alcohol while taking hydrocodone bitartrate and homatropine methylbromide. The co-ingestion of alcohol with hydrocodone bitartrate and homatropine methylbromide may result in increased plasma levels and a potentially fatal overdose of hydrocodone [see W arnings and Precautions (5.8) and Drug Interactions (7.1)] . Neonatal Opioid Withdrawal Syndrome Hydrocodone bitartrate and homatropine methylbromide is not recommended for use in pregnant women [see Use in Specific Populations (8.1)] . Prolonged use of hydrocodone bitartrate and homatropine methylbromide during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts. If hydrocodone bitartrate and homatropine methylbromide is used for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available [see Warnings and Precautions (5.13)] . WARNING: ADDICTION, ABUSE, AND MISUSE; LIFE- THREATENING RESPIRATORY DEPRESSION; ACCIDENTAL INGESTION; MEDICATION ERRORS; CYTOCHROME P450 3A4 INTERACTION; CONCOMITANT USE WITH BENZODIAZEPINES OR OTHER CNS DEPRESSANTS; INTERACTION WITH ALCOHOL; NEONATAL OPIOID WITHDRAWAL SYNDROME See full prescribing information for complete boxed warning. Hydrocodone bitartrate and homatropine methylbromide exposes users to risks of addiction, abuse, and misuse, which can lead to overdose and death. Assess patient’s risk before prescribing and monitor closely for these behaviors and conditions. (5.1) Serious, life-threatening, or fatal respiratory depression may occur. Monitor closely, especially upon initiation or when used in patients at higher risk. (5.2) Accidental ingestion of hydrocodone bitartrate and homatropine methylbromide, especially by children, can result in a fatal overdose of hydrocodone. (5.2) Ensure accuracy when prescribing, dispensing, and administering hydrocodone bitartrate and homatropine methylbromide. Dosing errors can result in accidental overdose and death. (2,1, 5.5) Concomitant use with CYP3A4 inhibitors (or discontinuation of CYP3A4 inducers) can result in a fatal overdose of hydrocodone. Avoid the use of hydrocodone bitartrate and homatropine methylbromide in patients taking CYP3A4 inhibitors or inducers. (5.7, 7.2, 7.3) Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Avoid the use of hydrocodone bitartrate and homatropine methylbromide in patients taking benzodiazepines, other CNS depressants, or alcohol. (5.8, 7.4) Instruct patients not to consume alcohol or any products containing alcohol while taking hydrocodone bitartrate and homatropine methylbromide because co-ingestion can result in fatal plasma hydrocodone levels. (5.8, 7.1) Hydrocodone bitartrate and homatropine methylbromide is not recommended for use in pregnant women. Prolonged use of hydrocodone bitartrate and homatropine methylbromide during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated. If hydrocodone bitartrate and homatropine methylbromide is used for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available. (5.13, 8.1)

Common side effects

• Follicular conjunctivitis
• Vascular congestion
• Edema
• Exudates
• Eczematoid dermatitis
• Thirst
• Dryness of mouth
• Eye irritation
• Increased sensitivity of eyes to light

Key clinical trials

• Non-Inferiority Comparison of Migrane® Versus Parcel ® For Treatment of Tensional Cephaleia (PHASE3)
• Effect of Systemic Oxygen on Corneal Epithelial Wound Healing in Diabetic Patients Undergoing Pars Plana Vitrectomy (NA)
• Intraoperative Dexamethasone Implant Improves Outcome of Cataract Surgery With Diabetic Macular Edema (PHASE4)
• The Role of Umbilical Cord Serum Therapy on Improvement of Corneal Epithelial Defect Following Diabetic Vitrectomy (PHASE1)

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Homatropin CI brief — competitive landscape report
• Homatropin updates RSS · CI watch RSS
• portfolio CI

Frequently asked questions about Homatropin

Related

• Drug class: All Cholinergic Muscarinic Antagonist drugs
• Target: All drugs targeting Muscarinic acetylcholine receptor M4
• Manufacturer: — full pipeline
• Therapeutic area: All drugs in Gastroenterology
• Indication: Drugs for Constipation
• Indication: Drugs for Cough
• Indication: Drugs for Cycloplegia

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing