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Generic Name: thiopental (THYE oh PEN tal)
Brand Name: Pentothal

What is Pentothal?

Pentothal is a barbiturate (bar-BIT-chur-ate). This medicine slows the activity of your brain and nervous system.

Pentothal is used to help you relax before you receive general anesthesia with an inhaled medication.

Pentothal may be used for other purposes not listed in this medication guide.

Important Information

You should not use Pentothal if you have porphyria, liver or kidney disease, severe anemia, myasthenia gravis, asthma, a thyroid disorder, or Addison's disease.

Before taking this medicine

You should not use Pentothal if you are allergic to it, or if you have:

  • porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system);

  • Addison's disease (an adrenal gland disorder);

  • liver or kidney disease;

  • severe anemia (low red blood cells);

  • a thyroid disorder;

  • myasthenia gravis;

  • asthma; or

  • if you are allergic to other barbiturates (amobarbital, butabarbital, mephobarbital, secobarbital, phenobarbital).

To make sure Pentothal is safe for you, tell your doctor if you have:

  • severe heart disease;

  • pituitary gland disorder;

  • a pancreas disorder;

  • head injury, brain tumor, or other condition that causes increased pressure inside the skull;

  • problems with the muscles in or around your eyes; or

  • if you take a blood thinner (warfarin, Coumadin, Jantoven).

FDA pregnancy category C. It is not known whether Pentothal will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using Pentothal.

Thiopental can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

How is Pentothal given?

Pentothal is injected into a vein through an IV. A healthcare provider will give you this injection.

You will be given this medication while you are lying down. You will fall asleep very quickly after Pentothal is injected.

Your breathing, blood pressure, oxygen levels, kidney function, and other vital signs will be watched closely while you are receiving Pentothal.

What happens if I miss a dose?

Since Pentothal is usually given just for anesthesia, you are not likely to be on a dosing schedule.

What happens if I overdose?

Since Pentothal is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

What should I avoid after receiving Pentothal?

Avoid drinking alcohol for at least 24 hours after you leave the hospital or surgery center.

Pentothal can cause severe drowsiness or dizziness, which may last for several hours. You will need someone to drive you home after your surgery or procedure. Do not drive yourself or do anything that requires you to be awake and alert for at least 24 hours.

Pentothal side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

You will remain under constant supervision during treatment with Pentothal. Your caregivers will watch for any serious side effects. Tell your caregivers at once if you have severe pain while receiving Pentothal.

Common side effects may include:

  • ongoing drowsiness;

  • weak or shallow breathing;

  • slow heartbeats;

  • chills or shivering;

  • sneezing, coughing, tight feeling in your throat; or

  • bronchospasm (wheezing, chest tightness, trouble breathing).

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Pentothal?

Other drugs may interact with thiopental, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.