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Nembutal Side Effects

Generic Name: pentobarbital

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

For the Consumer

Applies to pentobarbital: parenteral solution for injection

Side effects include:

Residual sedation, drowsiness, lethargy, vertigo, nausea, vomiting, headache.

For Healthcare Professionals

Applies to pentobarbital: compounding powder, injectable solution, oral capsule, oral elixir, rectal suppository

Nervous system

Common (1% to 10%): Somnolence

Uncommon (0.1% to 1%): Ataxia, central nervous system (CNS) depression, dizziness, hyperkinesia, syncope

Frequency not reported: Headache[Ref]


Uncommon (0.1% to 1%): Abnormal thinking, agitation, anxiety, confusion, dizziness, hallucination, nervousness, nightmares, psychiatric disturbance[Ref]


Uncommon (0.1% to 1%): Constipation, nausea, vomiting[Ref]


Uncommon (0.1% to 1%): Apnea, hypoventilation[Ref]


Uncommon (0.1% to 1%): Bradycardia, hypotension[Ref]


Frequency not reported: Angioedema, hypersensitivity reactions[Ref]


Frequency not reported: Exfoliative dermatitis, skin rashes[Ref]


Megaloblastic anemia occurred with chronic phenobarbital use.[Ref]

Frequency not reported: Megaloblastic anemia[Ref]


Frequency not reported: Liver damage[Ref]


Frequency not reported: Fever[Ref]


Frequency not reported: Injection site reactions[Ref]


1. "Product Information. Pentobarbital (pentobarbital)." Wyeth-Ayerst Laboratories, Philadelphia, PA.

2. "Product Information. Nembutal Sodium (pentobarbital)" 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.

More about Nembutal (pentobarbital)

Consumer resources

Other brands: Nembutal Sodium

Professional resources

Related treatment guides