Ciguatoxin's mechanism of action involves activation of voltage-dependent sodium channels. Tourists visiting the Caribbean may not develop symptoms until after returning home. Additionally, fish from tropical waters are now available globally, so cases are reported across the US mainland. While ciguatera poisoning rarely is fatal, morbidity may be high, and symptomatology may be prolonged. Death usually is attributed to cardiovascular depression, respiratory depression, or hypovolemic shock.
Most morbidity is neurological.
Neurologic symptoms resolve after 1-2 weeks, although pain, paraesthesia, pruritus, and weakness may persist for several weeks. Symptoms increase following ingestion of animal proteins. Chronic symptoms may occur and result in permanent nerve damage. Several reports show correlation between ethnic backgrounds and common symptom groupings. Children seem more severely affected and more often involved in life-threatening cases.