Bentyl vs. Donnatal

Are Bentyl and Donnatal the Same Thing?

Bentyl (dicyclomine) and Donnatal (belladonna alkaloids, phenobarbital) are used to treat irritable bowel syndrome (IBS).

Both Bentyl and Donnatal are anticholinergic drugs, and Donnatal also contains a barbiturate sedative.

Donnatal is also used to treat acute inflammation of the stomach and intestines (gastroenteritis) to reduce pain and diarrhea, and in patients with duodenal ulcer.

What Are Possible Side Effects of Bentyl?

Common side effects of Bentyl include:

What Are Possible Side Effects of Donnatal?

Common side effects of Donnatal include:

  • dizziness,
  • drowsiness,
  • weakness,
  • blurred vision,
  • dry eyes,
  • dry mouth,
  • nausea,
  • vomiting,
  • constipation,
  • abdominal bloating,
  • increased sensitivity to light,
  • decreased taste sensation,
  • decreased sweating or urination,
  • headache,
  • sleep problems (insomnia),
  • restlessness,
  • excitability,
  • impotence,
  • loss of interest in sex, or
  • trouble having an orgasm.

What is Bentyl?

Bentyl (dicyclomine) is an anticholinergics prescribed for irritable bowel syndrome (IBS).

What is Donnatal?

Donnatal (belladonna alkaloids, phenobarbital) is a combination of an anticholinergic/antispasmodic drug and a barbiturate sedative used to treat abdominal pain, bloating and cramps in patients with irritable bowel syndrome. Donnatal is also used to treat acute inflammation of the stomach and intestines (gastroenteritis) to reduce pain and diarrhea, and in patients with duodenal ulcer.


Digestive Disorders: Common Misconceptions See Slideshow

What Drugs Interact With Bentyl?

Bentyl may interact with amantadine, MAO inhibitors, phenothiazines, or antidepressants.

Bentyl may also interact with other medicines that make you sleepy (such as cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, or anxiety), digoxin, metoclopramide, atropine, belladonna, benztropine, dimenhydrinate, methscopolamine, scopolamine, bronchodilators, bladder or urinary medications, heart rhythm medications, irritable bowel medications, nitrates, steroids, or ulcer medications.

What Drugs Interact With Donnatal?

Products that may interact with Donnatal include blood thinners, ketoconazole, MAO inhibitors, bronchodilators, bladder or urinary medications or irritable bowel medications. Hormonal birth control products (pills, patch, ring) may not be effective if taken with Donnatal. Discuss all medications you are taking with your doctor. Donnatal is not recommended for use during pregnancy.

How Should Bentyl Be Taken?

The usual doses of Bentyl range from from 20 - 40 mg given 4 times daily.

How Should Donnatal Be Taken?

The dosage of Donnatal is adjusted to individual patients for symptomatic control with minimum adverse reactions. The usual dose is one tablet every 8 or 12 hours as prescribed.


What is irritable bowel syndrome or IBS? See Answer

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FDA. Bentyl Prescribing Information.
RedHill Pharma. Donnatal Prescribing Information.

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