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URL of this page: https://medlineplus.gov/druginfo/meds/a601024.html

Belladonna Alkaloid Combinations and Phenobarbital

pronounced as (bell a don' a) (fee noe bar' bi tal)

Why is this medication prescribed?

Belladonna alkaloid combinations and phenobarbital are used to relieve cramping pains in conditions such as irritable bowel syndrome and spastic colon. They also are used with other medicine to treat ulcers. These medicines decrease the motion of the stomach and intestines and the secretion of stomach fluids, including acid.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Belladonna alkaloid combinations and phenobarbital come as a regular tablet, a slow-acting tablet, capsule, and liquid to take by mouth. The regular tablet, capsule, and liquid are usually taken three or four times a day, 30 minutes before meals and at bedtime. The slow-acting tablet usually is taken two or three times a day at evenly spaced intervals. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take belladonna alkaloid combinations and phenobarbital exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Phenobarbital can be habit forming. Do not take a larger dose, take it more often, or for a longer period than your doctor tells you to. Signs of overdose are headache, nausea, vomiting, dizziness, blurred vision, dilated pupils in the eye, hot and dry skin, dry mouth, agitation, and difficulty swallowing. If you have any of these symptoms, stop taking belladonna alkaloids and phenobarbital and call your doctor immediately.

What special precautions should I follow?

Before taking belladonna alkaloid combinations and phenobarbital,

  • tell your doctor and pharmacist if you are allergic to belladonna, any barbiturate medicine, tartrazine (a yellow dye in some processed foods and drugs), or any drug.
  • Tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking belladonna alkaloid combinations and phenobarbital. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had glaucoma; an enlarged prostate; intestinal blockage; myasthenia gravis; hiatal hernia; ulcerative colitis (a condition which causes swelling and sores in the lining of the colon [large intestine] and rectum); kidney, heart, or liver disease; diseases of the urinary tract; or high blood pressure.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking belladonna alkaloids and phenobarbital, call your doctor.
  • talk to your doctor about the risks and benefits of taking this medication if you are 65 years of age or older. Older adults should receive low doses of belladonna and phenobarbital because higher doses do not function better and can cause serious side effects.
  • you should know that this drug may make you drowsy. Do not drive a car or operate machinery until you know how this drug affects you.
  • remember that alcohol can add to the drowsiness caused by this drug.
  • you should know that belladonna alkaloids may decrease sweating and cause heatstroke. Be careful of overheating during exercise and in hot weather.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

To avoid dry mouth or throat, chew gum or suck sugarless hard candies. To avoid increased eye sensitivity to light, wear sunglasses. Tell your doctor if any of these symptoms are severe or do not go away:

  • confusion
  • constipation
  • blurred vision
  • dizziness
  • drowsiness
  • nervousness
  • skin flushing

If you experience any of the following symptoms, call your doctor immediately:

  • eye pain
  • rapid heartbeat
  • skin rash
  • difficulty urinating
  • lack of sweating in hot weather

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else take your medicine. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names of combination products

  • Donnatal® Tablets (containing Atropine, Hyoscyamine, Phenobarbital, Scopolamine)
  • Donnatal® Elixir (containing Atropine, Hyoscyamine, Phenobarbital, Scopolamine)
  • PB Hyos® Elixir (containing Atropine, Hyoscyamine, Phenobarbital, Scopolamine)
  • Quadrapax® Elixir (containing Atropine, Hyoscyamine, Phenobarbital, Scopolamine)
Last Revised - 10/15/2023