MedlinePlus Drug Information: Pentobarbital Oral and Rectal

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Other drug names:	A-Am An-Az B C-Ch Ci-Cz D-Dh Di-Dz E F G H I-J K-L M-Mh Mi-Mz N-Nh Ni-Nz O P-Pl Pm-Pz Q-R S-Sn So-Sz T-To Tp-Tz U-V W-Z 0-9

Pentobarbital Oral and Rectal

(pen toe bar' bi tal)

Brand name(s): Nembutal

Contents of this page:
Why is this medication prescribed? How should this medicine be used? What special precautions should I follow? What should I do if I forget a dose?	What side effects can this medication cause? What storage conditions are needed for this medicine? In case of emergency/overdose What other information should I know?

Why is this medication prescribed?

Pentobarbital, a barbiturate, is used in the short-term treatment of insomnia (to help you fall asleep and stay asleep for a proper rest). It also is used as a sedative to relieve anxiety and induce sleep before surgery.

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

How should this medicine be used?

Pentobarbital comes as a capsule and liquid to take by mouth and as a suppository to be used rectally. The capsule or liquid is taken at bedtime as needed for insomnia or two to four times a day for anxiety. Take pentobarbital on an empty stomach, at least 1 hour before or 2 hours after meals. The suppositories are inserted at bedtime as needed for insomnia or two to four times a day for anxiety. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take pentobarbital exactly as directed.

Pentobarbital can be habit-forming; do not take a larger dose, take it more often, or for a longer time than your doctor tells you to. Do not stop taking pentobarbital without talking to your doctor, especially if you have taken large doses for a long time. Your doctor probably will decrease your dose gradually.

To insert a pentobarbital suppository, follow these steps:

Remove the wrapper.
Dip the tip of the suppository in water.
Lie down on your left side and raise your right knee to your chest. (A left-handed person should lie on the right side and raise the left knee.)
Using your finger, insert the suppository into the rectum, about 1/2 to 1 inch in infants and children and 1 inch in adults. Hold it in place for a few moments.
Stand up after about 15 minutes. Wash your hands thoroughly and resume your normal activities.

What special precautions should I follow?

Before taking pentobarbital,

tell your doctor and pharmacist if you are allergic to pentobarbital, aspirin, tartrazine (a yellow dye in some processed foods and drugs), or any other drugs.
tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially acetaminophen (Tylenol), antihistamines, chloramphenicol (Chloromycetin), digitoxin (Crystodigin), diuretics ('water pills'), doxycycline (Vibramycin), griseofulvin (Grisactin), medications for depression or seizures, metronidazole (Flagyl), oral contraceptives, propranolol (Inderal), quinidine, rifampin, sedatives, sleeping pills, steroids (for asthma), theophylline (Theo-Dur), tranquilizers, and vitamins.
tell your doctor if you have a fever or pain or if you have or have ever had liver or kidney disease, asthma, hyperthyroidism, diabetes, anemia, a history of alcoholism or drug abuse, or heart or lung problems.
tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking pentobarbital, call your doctor.
if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking pentobarbital.
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.

What should I do if I forget a dose?

Do not take a missed dose when you remember it. 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?

Although side effects from pentobarbital are not common, they can occur. Tell your doctor if any of these symptoms are severe or do not go away:

drowsiness
headache
depression
excitement
joint or muscle pain
upset stomach
diarrhea
constipation

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

skin rash
itching
sore throat
fever
easy bruising
bloody nose
unusual bleeding

What storage conditions are needed for this medicine?

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). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

In case of emergency/overdose

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

What other information should I know?

Keep all appointments with your doctor.

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

Last Revised - 01/01/2003

American Society of Health-System Pharmacists, Inc. Disclaimer