The article provides a comprehensive overview of acetylcholinesterase (AChE) inhibitors, focusing on their pharmacology and toxicology. AChE is an enzyme that breaks down the neurotransmitter acetylcholine (ACh), terminating impulse transmission in the nervous system. Inhibitors of AChE, whether reversible or irreversible, are used in various therapeutic and toxic contexts. Reversible inhibitors, such as donepezil, rivastigmine, and galantamine, are commonly used in the treatment of Alzheimer's disease (AD) by maintaining higher levels of ACh. Irreversible inhibitors, particularly organophosphorus compounds (OPs), are used in pesticides and nerve agents, causing severe toxicity due to their non-reversible phosphorylation of AChE. The article details the mechanisms of action, clinical applications, and detoxification processes for both types of inhibitors. For reversible inhibitors, oxime reactivators are used to restore enzyme activity after poisoning. For irreversible inhibitors, detoxification occurs through enzymatic hydrolysis by carboxylesterases (CESs) and phosphotriesterases (PTEs). The article also discusses the environmental and occupational risks associated with OPs and the importance of regulations to control their use.The article provides a comprehensive overview of acetylcholinesterase (AChE) inhibitors, focusing on their pharmacology and toxicology. AChE is an enzyme that breaks down the neurotransmitter acetylcholine (ACh), terminating impulse transmission in the nervous system. Inhibitors of AChE, whether reversible or irreversible, are used in various therapeutic and toxic contexts. Reversible inhibitors, such as donepezil, rivastigmine, and galantamine, are commonly used in the treatment of Alzheimer's disease (AD) by maintaining higher levels of ACh. Irreversible inhibitors, particularly organophosphorus compounds (OPs), are used in pesticides and nerve agents, causing severe toxicity due to their non-reversible phosphorylation of AChE. The article details the mechanisms of action, clinical applications, and detoxification processes for both types of inhibitors. For reversible inhibitors, oxime reactivators are used to restore enzyme activity after poisoning. For irreversible inhibitors, detoxification occurs through enzymatic hydrolysis by carboxylesterases (CESs) and phosphotriesterases (PTEs). The article also discusses the environmental and occupational risks associated with OPs and the importance of regulations to control their use.