Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

Quick facts

How it is given
oral
Type
human prescription drug
RxNorm ID
1047905

We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.

What it is used to treat

INDICATIONS AND USAGE Hyoscyamine Sulfate Tablets, USP are effective as adjunctive therapy in the treatment of peptic ulcer. They can also be used to control gastric secretions, visceral spasm and hypermotility in spastic colitis, spastic bladder, cystitis, pylorospasm and associated abdominal cramps. May be used in functional intestinal disorders to reduce symptoms such as those seen in mild dysenteries, diverticulitis and acute enterocolitis. For use as adjunctive therapy in the treatment of irritable bowel syndrome (irritable colon, spastic colon, mucous colitis) and functional gastrointestinal disorders. Also used as adjunctive therapy in the treatment of neurogenic bladder and neurogenic bowel disturbances (including the splenic flexure syndrome and neurogenic colon). Hyoscyamine Sulfate Tablets, USP are indicated along with morphine or other narcotics in symptomatic relief of biliary and renal colic; as a "drying agent" in the relief of symptoms of acute rhinitis; in the therapy of parkinsonism to reduce rigidity and tremors and to control associated sialorrhea and hyperhidrosis. May be used in the therapy of poisoning by anticholinesterase agents.

About this medicine

DESCRIPTION Hyoscyamine Sulfate Tablets, USP contain 0.125 mg hyoscyamine sulfate formulated for oral administration. Hyoscyamine sulfate is one of the principal anticholinergic/antispasmodic components of belladonna alkaloids. The empirical formula is (C 17 H 23 NO 3 ) 2 ∙H 2 SO 4 ∙2H 2 O and the molecular weight is 712.85. Chemically, it is benzeneacetic acid, α-(hydroxymethyl)-, 8-methyl-8-azabicyclo [3.2.1] oct-3-yl ester, [3(S)- endo ]-, sulfate (2:1), dihydrate with the following structure: Each tablet also contains as inactive ingredients: corn starch, lactose monohydrate, magnesium stearate, mannitol, stearic acid, and FD&C blue #1. Chemical Structure

Who should not take it

CONTRAINDICATIONS Glaucoma; obstructive uropathy (for example, bladder neck obstruction due to prostatic hypertrophy); obstructive disease of the gastrointestinal tract (as in achalasia, pyloroduodenal stenosis); paralytic ileus, intestinal atony of elderly or debilitated patients; unstable cardiovascular status in acute hemorrhage; severe ulcerative colitis; toxic megacolon complicating ulcerative colitis; myasthenia gravis.

Warnings

WARNINGS In the presence of high environmental temperature, heat prostration can occur with drug use (fever and heat stroke due to decreased sweating). Diarrhea may be an early symptom of incomplete intestinal obstruction, especially in patients with ileostomy or colostomy. In this instance, treatment with this drug would be inappropriate and possibly harmful. Like other anticholinergic agents, hyoscyamine sulfate may produce drowsiness, dizziness or blurred vision. In this event, the patient should be warned not to engage in activities requiring mental alertness such as operating a motor vehicle or other machinery or to perform hazardous work while taking this drug. Psychosis has been reported in sensitive individuals given anticholinergic drugs including hyoscyamine sulfate. CNS signs and symptoms include confusion, disorientation, short-term memory loss, hallucinations, dysarthria, ataxia, coma, euphoria, anxiety, decreased anxiety, fatigue, insomnia, agitation and mannerisms and inappropriate affect. These CNS signs and symptoms usually resolve within 12 to 48 hours after discontinuation of the drug.

Reported side effects

ADVERSE REACTIONS The following adverse reactions have been reported for hyoscyamine sulfate and for pharmacologically similar drugs with anticholinergic/antispasmodic action. Adverse reactions may include dryness of the mouth; urinary hesitancy and retention; blurred vision; tachycardia; palpitations; mydriasis; cycloplegia; increased ocular tension; loss of taste; headache; nervousness; drowsiness; weakness; fatigue; dizziness; insomnia; nausea; vomiting; impotence; suppression of lactation; constipation; bloated feeling; abdominal pain; diarrhea; allergic reactions or drug idiosyncrasies; urticaria and other dermal manifestations; ataxia; speech disturbance; some degree of mental confusion and/or excitement (especially in elderly persons); short-term memory loss; hallucinations; and decreased sweating. To report an adverse reaction, please contact Westminster Pharmaceuticals, LLC at 1-844-221-7294 or www.fda.gov/medwatch.

Interactions with other medicines

Drug Interactions Additive adverse effects resulting from cholinergic blockade may occur when hyoscyamine sulfate is administered concomitantly with other antimuscarinics, amantadine, haloperidol, phenothiazines, monoamine oxidase (MAO) inhibitors, tricyclic antidepressants or some antihistamines. Antacids may interfere with the absorption of hyoscyamine sulfate. Administer hyoscyamine sulfate before meals; antacids after meals.

If too much is taken

OVERDOSAGE The signs and symptoms of overdose are headache, nausea, vomiting, blurred vision, dilated pupils, hot dry skin, dizziness, dryness of the mouth, difficulty in swallowing and CNS stimulation. Measures to be taken are immediate lavage of the stomach and injection of physostigmine 0.5 to 2 mg intravenously and repeated as necessary up to a total of 5 mg. Fever may be treated symptomatically (tepid water sponge baths, hypothermic blanket). Excitement to a degree which demands attention may be managed with sodium thiopental 2% solution given slowly intravenously or chloral hydrate (100-200 mL of a 2% solution) by rectal infusion. In the event of progression of the curare-like effect to paralysis of the respiratory muscles, artificial respiration should be instituted and maintained until effective respiratory action returns. In rats, the LD50 for hyoscyamine is 375 mg/kg. Hyoscyamine sulfate is dialyzable.

Storing it safely

Store at controlled room temperature 20°C-25°C (68°F-77°F); excursion permitted to 15°C-30°C (59°F-86°F) see USP controlled room temperature. Dispense in tight, light-resistant containers as defined in USP/NF with a child-resistant closure. KEEP THIS AND ALL DRUGS OUT OF THE REACH OF CHILDREN.

Before you take anything new

Tell your pharmacist or doctor about every medicine you take — including ones bought without a prescription, herbal products and supplements. Interactions are one of the most common avoidable causes of harm from medicines, and a pharmacist can check your full list in a couple of minutes.


This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 1 June 2025. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.