Acetylcholine is not used commercially because:
Ref:KD Tripathi pharmacology 7th edition (page.no: 99) ACh is hydrolyzed by the enzyme cholinesterase and choline is recycled. A specific (Acetylcholinesterase-AChE or true cholinesterase) and a nonspecific (Butyrylcholinesterase-BuChE or pseudocholinesterase) type of enzyme occur in the body. So Ach is rapidly destroyed in the body
Long duration of action
Costly
rapidly destroyed in the body
Crosses blood brain barrier
Autonomic nervous system