MECHANISM: Abrupt withdrawal is thought to reduce inhibitory neurotransmission and enhance excitatory neurotransmission.
Caused by the effects of alcohol on GABA receptors (enhances γ-aminobutyric acid)
Constant consumption of alcoholic beverages will down regulate these GABA-receptors in order to maintain homeostasis!
There is a counter up regulation of excitatory neurotransmitters (i.e Glutamate) => Think of it like a see-saw trying to balance! (see image)
When alcohol is no longer consumed
Down-regulated GABA receptor complexes are so insensitive to GABA that the typical amount of GABA produced has little effect
Compounded with the fact that GABA normally inhibits action potential formation (there are not as many receptors for GABA to bind to aka Tachyphylaxis); sympathetic activation is unopposed!!! (i.e tachycardia, hypertension, tremulousness, and hyperreflexia)
Bayard M, McIntyre J, Hill KR, Woodside J Jr. Alcohol withdrawal syndrome. Am Fam Physician. 2004 Mar 15;69(6):1443-50.