Substance
Strychnine

Pathology
Competitive antagonism of glycine at postsynaptic spinal cord motor neuron.

Symptoms
Muscle twitching, extensor spasm, opisthotonos, trismus or facial grimacing, seizures, medullary paralysis, death. Symptoms occur within 20 min.

Emergency Measures
Activated charcoal; dark and quiet environment; benzodiazepines or neuromuscular blockade; mechanical ventilation.

Comments
Poisonings are rare since commercial use in rodenticides has decreased. Most exposures result in death. The approximate fatal dose for a child is 15 mg; for an adult, 5–10 mg/kg.