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Generic Name: Pentobarbital (pen toe BAR bi tal)
Brand Name: Nembutal

Uses of Pentobarbital:

  • It is used to treat sleep problems.
  • It is used to calm you before care.
  • It is used to treat seizures.
  • It is used to put you to sleep for surgery.
  • It may be given to you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take Pentobarbital?

  • If you have an allergy to pentobarbital or any other part of pentobarbital.
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you have ever had porphyria.
  • If you have liver disease.

This is not a list of all drugs or health problems that interact with pentobarbital.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take pentobarbital with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Pentobarbital?

  • Tell all of your health care providers that you take pentobarbital. This includes your doctors, nurses, pharmacists, and dentists.
  • Avoid driving and doing other tasks or actions that call for you to be alert until the effects of pentobarbital wear off and you feel fully awake.
  • Have your blood work checked if you are on pentobarbital for a long time. Talk with your doctor.
  • This medicine may be habit-forming with long-term use.
  • Use pentobarbital for short periods of time. If signs show up again, talk with the doctor.
  • If you have been taking pentobarbital for many weeks, talk with your doctor before stopping. You may want to slowly stop pentobarbital.
  • Avoid drinking alcohol while taking pentobarbital.
  • Talk with your doctor before you use other drugs and natural products that slow your actions.
  • This medicine may affect how much of some other drugs are in your body. If you are taking other drugs, talk with your doctor. You may need to have your blood work checked more closely while taking pentobarbital with your other drugs.
  • If you are 65 or older, use pentobarbital with care. You could have more side effects.
  • Studies in young animals and children have shown that frequent or long-term use of anesthesia drugs or drugs used for sleep in children younger than 3 years of age may lead to long-term brain problems. This may also happen in unborn babies if the mother uses pentobarbital during the third trimester of pregnancy. Talk with the doctor.
  • Birth control pills and other hormone-based birth control may not work as well to prevent pregnancy. Use some other kind of birth control also like a condom when taking pentobarbital.
  • This medicine may cause harm to the unborn baby if you take it while you are pregnant. If you are pregnant or you get pregnant while taking pentobarbital, call your doctor right away.
  • Long-term use of pentobarbital during pregnancy may cause dependence in the unborn baby or newborn. Talk with the doctor.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

How is this medicine (Pentobarbital) best taken?

Use pentobarbital as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • It is given as a shot into a muscle or vein.

What do I do if I miss a dose?

  • Call your doctor to find out what to do.

See also: Dosage Information (in more detail)

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Trouble breathing, slow breathing, or shallow breathing.
  • Very bad dizziness or passing out.
  • Feeling nervous and excitable.
  • Feeling confused.
  • Low mood (depression).
  • Feeling very tired or weak.
  • This medicine may cause tissue damage if the drug leaks from the vein. Tell your nurse if you have any redness, burning, pain, swelling, blisters, skin sores, or leaking of fluid where the drug is going into your body.

What are some other side effects of Pentobarbital?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Feeling sleepy.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at

See also: Side effects (in more detail)

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Pentobarbital?

  • If you need to store pentobarbital at home, talk with your doctor, nurse, or pharmacist about how to store it.

Consumer Information Use and Disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
  • Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about pentobarbital, please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Disclaimer: This information should not be used to decide whether or not to take pentobarbital or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about pentobarbital. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to pentobarbital. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using pentobarbital.

Review Date: March 7, 2018