Final answer:
Neostigmine (Prostigmin) works by inactivating acetylcholinesterase, preventing the breakdown of acetylcholine. It is absorbed in the gastrointestinal tract, and the duration of action varies depending on the route of administration.
Step-by-step explanation:
Neostigmine, also known as Prostigmin, works by inactivating the enzyme acetylcholinesterase, which prevents the breakdown of the neurotransmitter acetylcholine in the synapses. This action leads to both muscarinic and nicotinic effects.
Neostigmine is absorbed in the gastrointestinal (GI) tract when taken orally and is not absorbed through the skin or mucous membranes. It is also not absorbed well when injected intramuscularly or subcutaneously.
The duration of action of neostigmine varies depending on the route of administration. When given intramuscularly, the effects can last for 2 to 4 hours, while the duration is shorter when given intravenously or orally.