Diagnostic Considerations

The diagnosis in a severely intoxicated individual is straightforward. The combination of miosis, copious secretions, bronchospasm, generalized muscle fasciculations, and seizures is characteristic. Look carefully for miosis; it is diagnostically helpful, but miosis may not be present initially following a low volatility nerve agent exposure. GI symptoms by themselves could be confusing and they could be the only presenting manifestations.^[22]

In a child, a mild vapor exposure may mimic allergic rhinitis/conjunctivitis. Alternatively, a patient with mild vapor exposure may present with only visual complaints such as narrowing of the visual field or a sense that everything is going dark.^[22]

The differential diagnosis may include opioid overdose, which can cause miosis, apnea, and seizures.^[22]

Differential Diagnoses

Workup

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