Mechanism of Diazepam in Alcohol Withdrawal Syndrome

Neurobiological Basis

Chronic alcohol consumption enhances GABAergic inhibitory neurotransmission and suppresses glutamatergic excitatory neurotransmission in the brain 1
When alcohol is abruptly stopped, the brain experiences a sudden loss of GABA-mediated inhibition combined with unopposed glutamate-mediated excitation, leading to central nervous system hyperexcitability 1
This neurochemical imbalance manifests as the autonomic hyperactivity, tremors, anxiety, agitation, and potentially life-threatening complications (seizures, delirium tremens) characteristic of alcohol withdrawal syndrome 1, 2

Diazepam binds to benzodiazepine receptors on GABA-A receptor complexes, enhancing the inhibitory effects of GABA and restoring the balance between inhibitory and excitatory neurotransmission 1
This GABA activation produces multiple therapeutic effects: anxiety relief, sedation, muscle relaxation, and most critically, seizure prevention 1

Long-acting benzodiazepines like diazepam provide superior protection against seizures and delirium tremens compared to shorter-acting agents 1, 2, 3
Benzodiazepines are the only proven treatment to prevent seizures and reduce mortality from delirium tremens in alcohol withdrawal 3, 4
Anticonvulsants such as phenytoin or carbamazepine should not be used to prevent alcohol withdrawal seizures, as they are ineffective for this indication—the seizures result from rebound CNS hyperexcitability, not true epileptic activity 3

For patients with advanced liver disease, elderly patients, or those with respiratory compromise, lorazepam 6-12 mg/day is recommended as it has no active metabolites and shorter duration of action 1, 2, 3