Which of the following neurotransmitter systems is primarily dysregulated in alcohol withdrawal syndrome?

Explanation

## Neurochemical Basis of Alcohol Withdrawal ### GABA-Glutamate Imbalance **Key Point:** Chronic alcohol use enhances GABAergic (inhibitory) neurotransmission and suppresses glutamatergic (excitatory) neurotransmission. Upon abrupt cessation, this balance is lost, resulting in unopposed glutamatergic activity and CNS hyperexcitability. ### Mechanism of Withdrawal 1. **During chronic use:** Alcohol acts as a CNS depressant by potentiating GABA~A~ receptors and blocking NMDA glutamate receptors 2. **Neuroadaptation:** The brain compensates by downregulating GABA~A~ receptors and upregulating NMDA receptors 3. **Upon withdrawal:** Loss of alcohol's depressant effect leaves the brain in a state of unopposed excitation ### Clinical Manifestations Explained | Symptom | Mechanism | |---------|----------| | Tremor, tachycardia, hypertension | Sympathetic hyperactivity from CNS excitation | | Seizures | Threshold for neuronal firing dramatically lowered | | Hallucinations | Cortical hyperexcitability | | Delirium tremens | Severe glutamatergic excess + autonomic storm | **High-Yield:** The GABAergic-glutamatergic imbalance is the **fundamental mechanism** underlying all alcohol withdrawal syndromes—from mild tremor to life-threatening delirium tremens. **Clinical Pearl:** This is why benzodiazepines (GABA~A~ agonists) are the first-line treatment for alcohol withdrawal—they restore inhibitory tone and prevent seizures and delirium. ### Why Other Systems Are Secondary - Dopamine changes occur but are not the primary driver of withdrawal syndrome - Serotonin and cholinergic systems are affected but play minor roles compared to GABA-glutamate dysregulation