Editing Cholinergic (section)

== Cholinergic drug ==
{{Main|Parasympathomimetic drug}}

=== Structure activity relationship for cholinergic drugs ===
# A molecule must possess a nitrogen atom capable of bearing a positive charge, preferably a quaternary ammonium salt.
# For maximum potency, the size of the [[alkyl group]]s substituted on the nitrogen should not exceed the size of a [[methyl group]].
# The molecule should have an oxygen atom, preferably an [[ester]]-like oxygen capable of participating in a hydrogen bond.
# A two-carbon unit should occur between the oxygen atom and the nitrogen atom.
# There must be two methyl groups on the nitrogen
#A larger third alkyl group is tolerated but more than one large alkyl groups leads to loss of activity
#The overall size of the molecule cannot be altered much. Bigger molecules have poorer activity
<ref>{{Cite web |url=http://pharmaxchange.info/notes/medicinal_chemistry/adrenergics_cholinergics.html |title=Medicinal Chemistry of Adrenergics and Cholinergics |access-date=2010-10-23 |archive-url=https://web.archive.org/web/20101104022742/http://pharmaxchange.info/notes/medicinal_chemistry/adrenergics_cholinergics.html |archive-date=2010-11-04 |url-status=dead }}</ref>