What mechanism does physostigmine use to exert its effects?

Physostigmine exerts its effects primarily through the deactivation of acetylcholinesterase, an enzyme responsible for the breakdown of the neurotransmitter acetylcholine in the synaptic cleft. By inhibiting acetylcholinesterase, physostigmine increases the availability of acetylcholine, enhancing cholinergic transmission. This mechanism helps improve cognitive function and can be particularly useful in conditions characterized by acetylcholine deficiency, such as myasthenia gravis or Alzheimer's disease.

This increase in acetylcholine levels leads to enhanced stimulation of nicotinic and muscarinic receptors throughout the nervous system, resulting in improved neuromuscular transmission and various physiological effects associated with cholinergic activity. Understanding this mechanism is crucial for interpreting the pharmacological applications of physostigmine in clinical settings.