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Thiopental Side Effects

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: 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.

Further information

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

Some side effects may not be reported. You may report them to the FDA.