injuries poisoning
Organophosphate Poisoning and Carbamate Poisoning
Introduction
Organophosphates and carbamates are common insecticide ingredients that inhibit cholinesterase activity, causing acute muscarinic manifestations (eg, salivation, lacrimation, urination, diarrhea, emesis, bronchorrhea, bronchospasm, bradycardia, miosis) and some nicotinic symptoms, including muscle fasciculations and weakness. Neuropathy can develop days to weeks after exposure. Diagnosis is clinical and sometimes with a trial ofatropine, measurement of red blood cell acetylcholinesterase level, or both. Bronchorrhea and bronchospasm are treated with titrated high-doseatropine. Neuromuscular toxicity is treated with IVpralidoxime. (See also General Principles of Poisoning .) Organophosphates and carbamates, although different structurally, both inhibit cholinesterase activity. Some are used medically to reverse neuromuscular blockade (eg,neostigmine,pyridostigmine, edrophonium) or to treat glaucoma (echothiopate), myasthenia gravis (pyridostigmine), and Alzheimer disease (tacrine anddonepezil). Some organophosphates were developed as Nerve Chemical-Warfare Agents for use in warfare. One, sarin, has been used by terrorists. Organophosphates and carbamates are commonly used as insecticides (see table Carbamates: Aldicarb and methomyl Organophosphates: Chlorpyrifos, diazinon, dursban, fenthion,malathion, and parathion Organophosphates and carbamates are common causes of poisoning and poison-related deaths worldwide. 