Carbachol is an directly acting cholinergic drug, directly interacting with the cholinergic recpetor. Chemically it is a Choline ester. It is also called as cholinomimetic and parasympathomimetic. 
 
IUPAC Name - 2-carbamoyloxyethyl(trimethyl)azanium;chloride

Synthesis

From Carbamic Acid
Step 1 : Carbamic acid is reacted with dichloro ethane. Simple condensation reaction takes place, HCl is removed, Chloroethyl urethane is formed.

Step 2 : To chloroethyl urethane, Trimethyl amine is added (Ammonia, in which all hydrogen is replaced with methyl), carbachol results.

carbachol

Mechanism of Action

        It possess both muscarinic and nicotinic properties by cholinergic receptor stimulation.

Uses

        It is used for its miotic actions in the treatment of glaucoma to reduce intraocular pressure.

Adverse effects

        No frequent / severe adverse effects