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Pentothal Side Effects

Generic Name: thiopental

Note: This document contains side effect information about thiopental. Some of the dosage forms listed on this page may not apply to the brand name Pentothal.

For the Consumer

Applies to thiopental: intravenous powder for injection

Get emergency medical help if you have any of these signs of an allergic reaction while taking thiopental (the active ingredient contained in Pentothal) hives; difficult breathing; swelling of your face, lips, tongue, or throat.

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

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.

For Healthcare Professionals

Applies to thiopental: intravenous powder for injection, rectal suspension


Cardiovascular side effects have included myocardial depression, cardiac arrhythmias, and a fall in blood pressure even to shock levels.[Ref]


Respiratory side effects have included respiratory depression, sneezing, coughing, bronchospasm, and laryngospasm.[Ref]

Nervous system

Nervous system side effects have included prolonged somnolence and recovery. Radial nerve palsy has been reported rarely.[Ref]


Hypersensitivity side effects have included anaphylactic and anaphylactoid reactions, e.g., urticaria, bronchospasm, vasodilation and edema.[Ref]


General side effects have included shivering.[Ref]


Hematologic side effects have included rare reports of immune hemolytic anemia with renal failure.[Ref]


1. "Product Information. Pentothal (thiopental)." Abbott Pharmaceutical, Abbott Park, IL.

Some side effects of Pentothal may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.