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Organophosphates are usually dissolved in hydrocarbon bases; thus, the
clinician should be prepared to treat potential hydrocarbon pneumonitis.
Carbamate insecticides have a similar mechanism of action to organophosphate
insecticides but the phosphorylation of acetylcholinesterase is reversible and
temporary. Pralidoxime therapy is generally regarded as unnecessary after
poisoning from carbamates.

Rodenticides
Long-acting vitamin K antagonists (VKAs) are commonly used rodenticides.
They work similarly to warfarin anticoagulants by inhibition of the vitamin K
cycle, leading to a reduction in the cyclic activation of vitamin K, which is an
essential cofactor in the synthesis of clotting factors II, VII, IX, and X. Because
long-acting VKAs are highly lipid soluble and concentrate in the liver, they are
more potent and have a significantly longer duration of action than warfarin.
Intentional ingestions of long-acting VKAs can lead to severe, prolonged
coagulopathy lasting weeks to months. Patients with acute intentional ingestions
should have daily INR testing for 2 days to monitor for development of
coagulopathy. Those with coagulopathy require acute management of bleeding
and prolonged treatment with high doses of vitamin K. However, children with
unintentional ingestions are unlikely to develop coagulopathy due to the small
amount ingested in a taste of a rodenticide pellet. Therefore, children with small
unintentional exposures should have follow-up with an INR 48 to 72 hours after
exposure. A baseline INR is usually not necessary unless there is concern for
chronic exposure or underlying coagulopathy.
See Table 102.17 for a summary of other rodenticides and their toxicities.