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 Answer
Which 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)