What You Need to Know About Donnatal (Belladonna/Phenobarbital)


Donnatal is a type of drug called an anticholinergic and is actually a combination of two drugs: belladonna and phenobarbital. It is used to relax the muscles in the bladder and the intestines as well as to reduce stomach acid. It's also important to know that phenobarbital is a mild sedative.

The Habit-Forming Potential of Donnatal

Phenobarbital can be habit-forming. Donnatal may not be an appropriate treatment for people who have been dependant on other drugs. Before taking donnatal, talk to your doctor if you have had difficulty with drug dependence or alcoholism in the past. Being chemically dependant on a drug means that there are physiologic reactions when the drug is withdrawn.

How It's Taken


Why It's Prescribed

Donnatal is used to treat irritable bowel syndrome (IBS), diverticulosis, and bladder spasms. It may be prescribed for other conditions.

What to Do After Missing a Dose


Who Should Not Take Donnatal

Before taking Donnatal, tell a doctor if any of these conditions are occurring now or have occurred in the past:

Potential Side Effects of Donnatal

The most serious side effects of Donnatal are confusion, blurred vision, difficulty in urination, and decreased sweating. If these symptoms occur after taking Donnatal, seek medical attention immediately. Take care to stay hydrated while taking this drug, particularly in hot weather, because it can cause dehydration.

Other common side effects that are usually not as serious include headache, nausea, constipation, rash, and vomiting. See a doctor if any of these side effects become severe or are bothersome.

Medications That Can Interact With Donnatal


  • Antacids
  • Antidepressants
  • Antihistamines
  • Antispasmodics
  • Barbiturates
  • Birth Control Pills
  • Blood-thinning drugs (Coumadin)
  • Cimetidine (Tagamet)
  • Diarrhea medications containing Kaolin or attapulgite
  • Digitalis (Lanoxin)
  • Metoclopramide (Reglan)
  • Monoamine oxidase (MAO) inhibitors
  • Narcotics
  • Potassium chloride
  • Prednisone
  • Sedatives
  • Thiazide diuretics

Potential Food Interactions

Consuming alcohol while taking Donnatal could increase the sedative effect and cause tiredness or sleepiness. Take care to avoid alcohol from unexpected sources, such as over the counter cough suppressants or cold products (Nyquil, for example).

Safety During Pregnancy


Donnatal should only be used during pregnancy if it is clearly needed. Women should call their doctor upon becoming pregnant while taking Donnatal. The potential for serious side effects in an infant should be weighed against the usefulness of the medication to the mother.

Potential Sexual Side Effects


A Word From Verywell

Donnatal can be helpful in relieving pain or discomfort for people who are living with bowel and bladder conditions. However, it does carry a risk of dependency, which may mean that it is not a good choice for people who have experienced chemical dependency in the past. This drug is usually prescribed to be taken when it is needed, such as after a meal. In the beginning, it may be helpful to take this drug at night to see if it causes a sedative effect. Once the potential side effects are better understood, it may be possible to take this drug at other times if it doesn't cause drowsiness.

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