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Thiopental Side Effects

Medically reviewed by Last updated on Mar 3, 2023.

Applies to thiopental: intravenous powder for injection, rectal suspension.


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

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:

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.


Rare (less than 0.1%): Anaphylactoid reactions (e.g., urticaria, bronchospasm, fall in blood pressure, angioedema)

Frequency not reported: Allergic reactions, hypersensitivity, anaphylactic shock[Ref]


Common (1% to 10%): Pain at the administration site[Ref]


Frequency not reported: Involuntary movements, muscle tremor[Ref]


Frequency not reported: Hypokalemia, hyperkalemia, anorexia[Ref]


Frequency not reported: Unpleasant dream, euphoria, dysphoria[Ref]


Common (1% to 10%): Respiratory depression, bronchospasm, laryngospasm, coughing, snoring, sneezing[Ref]


Common (1% to 10%): Shivering

Frequency not reported: Malaise, fatigue[Ref]

Nervous system

Common (1% to 10%): Somnolence, delayed wakening

Frequency not reported: Headache, confusion, dizziness, amnesia[Ref]


Frequency not reported: Renal failure, polyuria (when high doses are used)[Ref]


Common (1% to 10%): Heart arrhythmia, myocardia depression, hypotension, thrombosis, phlebitis

Frequency not reported: Tachycardia[Ref]


Frequency not reported: Skin reactions[Ref]


Frequency not reported: Nausea, vomiting[Ref]


1. Cerner Multum, Inc. UK Summary of Product Characteristics.

2. Cerner Multum, Inc. Australian Product Information.

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.