Organophosphates toxicity

Learning objectives

Organophosphates toxicity often results from contact with organophosphate insecticides
The majority of organophosphate toxicity occurs in farmers and people who work in agriculture
The onset of symptoms is often within minutes and can persist for weeks
Organophosphate pesticide exposure may occur through inhalation, ingestion, or dermal contact
Organophosphate insecticides inhibit carboxyl ester hydrolases and mainly acetylcholinesterase (AChE), an essential enzyme in the breakdown of acetylcholine
Resulting in the accumulation of acetylcholine and overstimulation of the nicotinic and muscarinic receptors
Organophosphates stimulate both the sympathetic and parasympathetic nervous systems

Mnemonics to remember the symptoms and the responsible receptor:

For nicotinic signs of acetylcholinesterase inhibitor toxicity, think of the days of the week:	The more common mnemonic that captures the muscarinic effects of organophosphate poisonings is DUMBELS:	Additional symptoms
Monday = Mydriasis Tuesday = Tachycardia Wednesday = Weakness Thursday = Hypertension Friday = Fasciculations	D = Defecation/diaphoresis U = Urination M = Miosis B = Bronchospasm/bronchorrhea E = Emesis L = Lacrimation S = Salivation	Increased saliva and tear production Diarrhea Vomiting Small pupils Sweating Muscle tremors Anxiety Confusion Drowsiness Emotional lability Seizures Hallucinations Headaches