Nicotinic antagonist

A nicotinic antagonist is a type of anticholinergic drug that inhibits the action of acetylcholine at nicotinic [acetylcholine receptor]s. These compounds are mainly used for peripheral muscle paralysis in surgery, the classical agent of this type being tubocurarine, but some centrally acting compounds such as bupropion, mecamylamine, and 18-methoxycoronaridine block nicotinic acetylcholine receptors in the brain and have been proposed for treating nicotine addiction.

Mechanism	Antagonist	Preferred receptor	Clinical use	-
Ganglionic blocking agents	Hexamethonium	Ganglion type	-	-
Ganglionic blocking agents	Mecamylamine	Ganglion type		-
Ganglionic blocking agents	Trimethaphan	Ganglion type	Rarely used for blood pressure decrease during surgery	-
Nondepolarizing neuromuscular blocking agents	Atracurium	Muscle type	Muscle relaxant in anaesthesia	-
Nondepolarizing neuromuscular blocking agents	Doxacurium	Muscle type		-
Nondepolarizing neuromuscular blocking agents	Mivacurium	Muscle type		-
Nondepolarizing neuromuscular blocking agents	Pancuronium	Muscle type	Muscle relaxant in anaesthesia	-
Nondepolarizing neuromuscular blocking agents	Tubocurarine	Muscle type	Discovered in arrow poison; it was the first peripheral muscle relaxant. Rarely used since the 1980s.	-
Nondepolarizing neuromuscular blocking agents	Vecuronium	Muscle type	Muscle relaxant in anaesthesia	-
Depolarizing neuromuscular blocking agents	Succinylcholine*	Muscle type		-
Centrally acting nicotinic antagonists	18-Methoxycoronaridine	α3β4		-
Centrally acting nicotinic antagonists	Bupropion	α3β4. α4β2, α1β1γδ	Antidepressant
Centrally acting nicotinic antagonists	Hydroxybupropion	α3β4. α4β2, α1β1γδ	Antidepressant. Metabolite of bupropion.
Centrally acting nicotinic antagonists	Threohydrobupropion	α3β4.	Antidepressant. Metabolite of bupropion.
Centrally acting nicotinic antagonists	Dextromethorphan	α3β4. α4β2, α7	Common over the counter antitussive.	-
Centrally acting nicotinic antagonists	Dextrorphan	α3β4. α4β2, α7	Metabolite of dextromethorphan; no accepted medical uses.	-
Centrally acting nicotinic antagonists	3-Methoxymorphinan	α3β4	Secondary metabolite of dextromethorphan; not used in medical practice. Unknown medical efficacy.	-

Note: Succinylcholine is a nicotinic agonist. See neuromuscular blocking agents page for details on the mechanism of action.