General Measures in the Management of Acute Pesticide Poisoning

I. Emergency stabilization

D. Treat convulsions
Convulsions in poisoned patients may be due to:

1. Direct convulsant effect of pesticides
2. Cerebral hypoxia from respiratory or cardiovascular complications of pesticides
3. Hypoglycemia
4. Severe muscle spasm due to spinal or peripheral effects on the mechanism controlling muscle tone
5. Decreased seizure threshold in an epileptic patient.

General management for seizures:
Diazepam
Adult: 5 mg slow IV push
Pedia: 0.3 mg/kg/dose slow IV push
This may be repeated every 2-5 minutes up to a maximum dose of 20 mg. If the dose exceeds 20 mg, intubation and artificial respiratory support may have to be done before giving additional diazepam. Never dilute diazepam with any fluid.
Lorazepam
Adult: 2.5-10 mg/dose repeated twice at intervals of 15-20 min prn. Usual dose is 4-5 mg/dose. Pedia: 0.05-0.1 mg/kg/dose IV up to max of 4 mg/dose repeated twice at intervals of 10-15 min prn.
Compatible with D5W.

Management of uncontrolled seizures:
Phenytoin
Loading dose: 15 - 20 mg/kg slow IV push at a rate not to exceed 50 mg/minute (adults) or 1mg/kg/minute (pedia).
Maintenance dose:
Adult: 100 mg PO or IV every 6 to 8 hours
Pedia: 5-7 mg/kg/day in divided doses
Phenytoin should never be diluted in dextrose containing fluids to avoid crystallization.

Both diazepam and phenytoin are poorly absorbed and are ineffective when given through the intramuscular route. In emergency situations, Lorazepam is particularly useful since it can be given IV or IM.