Pentobarbital (By mouth)

Pentobarbital (pen-toe-BAR-bi-tal)

Treats insomnia (trouble sleeping). Also helps you relax before having surgery or a medical procedure. This medicine is a barbiturate.

Brand Name(s):

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

You should not use this medicine if you have had an allergic reaction to pentobarbital or other barbiturates (such as phenobarbital), if you have porphyria, or if you are pregnant.

How to Use This Medicine:

Capsule

  • Your doctor will tell you how much medicine to use. Do not use more than directed.
  • This medicine is not for long-term use.
  • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
  • If you are taking this medicine for insomnia, take it only at bedtime.
  • Never share your medicine with anyone.

How to Store and Dispose of This Medicine:

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are also using blood thinners (Coumadin®), corticosteroids (cortisone, prednisone), griseofulvin (Grifulvin®), doxycycline (Vibramycin®), medicine for seizures (such as Depakote®, Dilantin®), MAO inhibitors (such as Eldepryl®, Marplan®, Nardil®, or Parnate®), or hormones (including birth control pills).
  • Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.
  • Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

  • It is not safe to take this medicine during pregnancy. It could harm an unborn baby. Tell your doctor right away if you become pregnant.
  • Make sure your doctor knows if you are breastfeeding, or if you have liver disease, kidney disease, food or drug allergies, a history of alcohol or drug abuse, or have any health problems that cause pain.
  • Tell your doctor if you feel depressed or have thoughts of suicide.
  • This medicine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Stop taking this medicine and call your doctor right away if you have itching, hives, trouble breathing, or any swelling of your hands, face, or mouth when you take this medicine.
  • This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert. This medicine may also cause sleep-related behaviors such as sleep-driving, making phone calls, or preparing and eating food while asleep or not fully awake. If these reactions occur, tell your doctor right away.
  • This medicine can be habit-forming. Do not use more than your prescribed dose. Call your doctor if you think your medicine is not working.
  • Taking too much of this medicine can cause serious breathing problems. Symptoms of an overdose include: Extreme dizziness or fainting, shortness of breath or shallow breathing, fast heartbeat, and low body temperature.
  • Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.
  • If you have any of these symptoms after you stop taking pentobarbital, call your doctor right away: Anxiety, trembling or twitching, weakness, trouble seeing, dizziness, confusion, or seizures.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Muscle weakness or uncontrolled body movements.
  • Slow heartbeat.
  • Trouble breathing.
  • Unusual thoughts or behavior, confusion, or hallucinations.
  • Yellowing of your skin or the whites of your eyes.

If you notice these less serious side effects, talk with your doctor:

  • Dizziness or lightheadedness.
  • Mild fever.
  • Nausea, vomiting, or constipation.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088


Last Updated: 9/6/2024

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