pralidoxime chloride /pral″ədok′sēm/ , a cholinesterase reactivator. ▪ INDICATIONS: It is prescribed as an antidote for organophosphate poisoning and drug overdosage in the treatment of myasthenia gravis. ▪ CONTRAINDICATIONS: Known hypersensitivity to this drug prohibits its use. It is contraindicated in poisoning by carbamate insecticides that react with pralidoxime. ▪ ADVERSE EFFECTS: Among the most serious adverse effects are dizziness, tachycardia, hyperventilation, and muscle weakness. These reactions are most common when the drug is injected too rapidly.