Under normal conditions in the brain, there is a balance between excitatory neurotransmitters such as glutamate and inhibitory neurotransmitters such as  gamma-aminobutyric acid (GABA). Chronic alcohol intake and acute discontinuation of alcohol intake affect the balance of the neurotransmitters and cause many of the symptoms observed in alcohol withdrawal.
Alcohol withdrawal pathophysiology
Tricyclic antidepressant overdose pathophysiology
Short-term effects of alcohol
Heat stroke pathophysiology
Alcoholism pathophysiology
Opiate withdrawal
Opioid withdrawal
Opioid indications