Abrupt withdrawal from chronic barbiturate use may progress to which life-threatening event?

• A. Severe hallucinations.
• B. Hyperglycemia.
• C. Kidney failure.
• D. Cardiovascular collapse and death.

Answer: (D)

Abrupt withdrawal from chronic barbiturate use can trigger a rebound state of CNS and autonomic hyperactivity due to loss of GABAergic inhibition. Long-term barbiturate exposure trains the brain to rely on the drug’s enhancement of GABA-A–mediated inhibition. When the drug is suddenly stopped, that inhibitory control wanes, and the result is an intense sympathetic surge, seizures, and delirium. The severe autonomic “storm”—tachycardia, hypertension, hyperthermia, and potential hypoxia from seizures—can progress to cardiovascular instability and shock, sometimes culminating in death. That ominous potential is why cardiovascular collapse is the life-threatening consequence associated with abrupt withdrawal.

Other symptoms like hallucinations can occur during withdrawal, but they don’t carry the same immediate risk of fatal cardiovascular collapse as the autonomic instability and seizures do. Hyperglycemia or kidney failure are not typical acute withdrawal complications of barbiturates.