- What is hyoscyamine, atropine, scopolamine, phenobarbital, and how does it work (mechanism of action)?
- What are the uses for hyoscyamine, atropine, scopolamine, phenobarbital?
- What are the side effects of hyoscyamine, atropine, scopolamine, phenobarbital?
- What is the dosage for hyoscyamine, atropine, scopolamine, phenobarbital?
- Which drugs or supplements interact with hyoscyamine, atropine, scopolamine, phenobarbital?
- Is hyoscyamine, atropine, scopolamine, phenobarbital safe to take if I'm pregnant or breastfeeding?
- What else should I know about hyoscyamine, atropine, scopolamine, phenobarbital?
What is hyoscyamine, atropine, scopolamine, phenobarbital, and how does it work (mechanism of action)?
Belladonna/phenobarbital is an oral medication which combines naturally occurring belladonna alkaloids (atropine, scopolamine [Transderm-Scop], and hyoscyamine) with phenobarbital. It is used for treating abdominal discomfort that is thought to be due to muscular spasm of the intestinal muscles. Belladonna alkaloids block the action of acetylcholine, a chemical that nerves to use to communicate with other nerves and muscles. Acetylcholine stimulates the muscles of the intestines that propels digesting food through the intestine. It also affects the secretion of fluids by salivary glands and the stomach. By blocking acetylcholine, belladonna alkaloids relax intestinal muscles, slow passage of digesting food through the intestines, and reduce gastric secretion. Phenobarbital produces sedation. The FDA classifies Belladonna/phenobarbital as possibly effective for its stated uses.
What brand names are available for hyoscyamine, atropine, scopolamine, phenobarbital?
Donnatal, Donnatal Extentabs
Is hyoscyamine, atropine, scopolamine, phenobarbital available as a generic drug?
GENERIC AVAILABLE: Yes
Do I need a prescription for hyoscyamine, atropine, scopolamine, phenobarbital?
Yes
What are the uses for hyoscyamine, atropine, scopolamine, phenobarbital?
Belladonna/phenobarbital is used in the treatment of abdominal pain, bloating and cramps in patients with irritable bowel syndrome. It is also used in patients with acute inflammation of the stomach and intestines (gastroenteritis) to reduce pain and diarrhea. It is used occasionally as additional therapy in patients with duodenal ulcer.
What are the side effects of hyoscyamine, atropine, scopolamine, phenobarbital?
Adverse reactions include:
- constipation;
- dry eyes;
- dry mouth;
- urinary hesitancy and retention (difficulty urinating, particularly in men);
- blurred vision;
- rapid heart rate;
- palpitations;
- headache;
- nervousness;
- drowsiness; and
- dizziness
Caution is advised in patients with glaucoma, myasthenia gravis and urinary obstruction since symptoms of these conditions may worsen with the use of belladonna/phenobarbital. Patients with an unstable cardiac status, severe ulcerative colitis and acute intermittent porphyria should avoid belladonna/phenobarbital. Elderly patients may experience confusion, depression, and excitement even from small doses.
What is the dosage for hyoscyamine, atropine, scopolamine, phenobarbital?
May be taken with or without food. The dosage is adjusted to the individual patient to assure control of symptoms with a minimum of side effects. The usual doses are 1-2 regular tablets 3 to 4 times daily or 1 extended release tablet every 8 or 12 hours or 5-10 ml of the elixir, 3 or 4 times daily.

QUESTION
What is irritable bowel syndrome or IBS? See AnswerWhich drugs or supplements interact with hyoscyamine, atropine, scopolamine, phenobarbital?
Phenobarbital reduces the blood levels of several drugs by increasing their breakdown in the body. Examples include voriconazole (Vfend), bocepravir (Victrelis), ranolazine (Ranexa), and protease inhibitors (for example, atazanavir [Reyataz], indinavir [Crixivan], saquinavir [Invirase], ritonavir [Norvir]). Belladonna/phenobarbital should not be combined with potassium tablets because belladonna/phenobarbital slows the passage of potassium tablets through the gastrointestinal tract, leading to potassium-induced ulcers and high potassium levels in the blood.
Is hyoscyamine, atropine, scopolamine, phenobarbital safe to take if I'm pregnant or breastfeeding?
Use during pregnancy has not been adequately evaluated. Pregnant women should use belladonna alkaloid/phenobarbital only when the expected benefit outweighs the potential but unknown risks. Belladonna/phenobarbital are secreted in breast milk and may also reduce milk production.
What else should I know about hyoscyamine, atropine, scopolamine, phenobarbital?
What preparations of hyoscyamine, atropine, scopolamine, phenobarbital are available?
- Tablets: 16.2 mg phenobarbital, 0.1037 mg hyoscyamine sulfate, 0.0194 mg atropine sulfate, and 0.065 mg scopolamine hydrobromide
- Sustained release tablets: 48.6 mg phenobarbital, 0.311 mg hyoscyamine sulfate, 0.0582 mg atropine sulfate, and 0.0195 mg scopolamine hydrobromide.
- Elixir (per 5ml): 16.2 mg phenobarbital, 0.1037 mg hyoscyamine sulfate, 0.0194 mg atropine sulfate, and 0.0065 mg scopolamine hydrobromide.
How should I keep hyoscyamine, atropine, scopolamine, phenobarbital stored?
Belladonna/phenobarbital should be stored at controlled room temperature between 15-30 C (59-86 F)
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Summary
Hyoscyamine sulfate, atropine sulfate, scopolamine sulfate and phenobarbital (Donnatal, Donnatal Extentabs) is a medication prescribed for the treatment of abdominal pain, bloating, and cramps in patients with IBS (irritable bowel syndrome), and gastroenteritis. Review side effects, drug interactions, warnings and precautions, and pregnancy safety information prior to taking any medication.
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Related Disease Conditions
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Stomach Flu (Gastroenteritis)
Stomach flu (gastroenteritis) is a term referred used to describe a variety of gastrointestinal problems. The most common signs and symptoms of gastroenteritis are nausea, vomiting, diarrhea, and abdominal pain. The most common cause of gastroenteritis in the United States is Norovirus. Other causes of gastroenteritis include Rotavirus, Astrovirus, Adenovirus, and Sapovirus. There are bacterial causes of gastroenteritis such as Salmonella, Shigella, Campylobacter Aeromonas, E. coli, Clostridium, Vibrio, Campylobacter, and Yersinia spp. Parasites that cause gastroenteritis include Giardia, Cryptosporidium, Cyclospora, and Entamoeba. Treatment for gastroenteritis is generally home remedies such as keeping hydrated to prevent dehydration. At times, hospitalization may be necessary if dehydration occurs.
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Intestinal Gas and Gas Pain
Intestinal gas and painful bloating are common. Learn about what causes gas pain and how eliminating certain foods from your diet can help relieve symptoms.
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Irritable Bowel Syndrome (IBS)
Irritable bowel syndrome or IBS is a GI disorder with symptoms of constipation, abdominal pain, bloating, and gas. IBS treatment includes medications, dietary changes, and lifestyle changes.
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Colitis
Colitis refers to inflammation of the inner lining of the colon. Symptoms of the inflammation of the colon lining include diarrhea, pain, and blood in the stool. There are several causes of colitis, including infection, ischemia of the colon, inflammatory bowel disease (Crohn's disease, ulcerative colitis, infectious colitis like C. difficile, or microscopic colitis). Treatment depends on the cause of the colitis.
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Diverticulitis (Diverticulosis)
Most people with diverticulosis have few if any symptoms at all. When people do experience signs and symptoms of diverticulosis (diverticular disease) they may include abdominal pain, abdominal cramps, diarrhea, constipation, and bloating. Diverticulitis is a condition in which diverticula in the colon rupture. The rupture results in infection in the tissues that surround the colon. Treatment methods for diverticulitis include prescription medications, and in some cases, diverticulitis surgery.
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Abdominal Pain
Abdominal pain can have many causes that range from mild to severe. Some of these causes include bloating, gas, colitis, endometriosis, food poisoning, GERD, IBS (irritable bowel syndrome), ovarian cysts, abdominal adhesions, diverticulitis, Crohn's disease, ulcerative colitis, gallbladder disease, liver disease, and cancers. Signs and symptoms of the more serious causes include dehydration, bloody or black tarry stools, severe abdominal pain, pain with no urination or painful urination. Treatment for abdominal pain depends upon the cause.
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Indigestion (Dyspepsia, Upset Stomach Pain)
Indigestion (dyspepsia, upset stomach) can be caused by problems related to, or not related to the gastrointestinal tract. Signs and symptoms are upper abdominal pain, belching, nausea, vomiting, abdominal bloating, and abdominal distention. Treatment depends upon the cause.
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Bowel Incontinence (Fecal Incontinence)
Bowel or fecal incontinence refers to the loss of voluntary control of stool, or bowel movements. The condition can include partial incontinence, in which a person loses only a small amount of liquid waste, to complete incontinence, in which the entire bowel movement cannot be controlled. Diet changes and elimination of certain medications can help patients to regain bowel control. Treatment involves a combination of medication, biofeedback, and exercise.
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