Patient with purely extraocular manifestations from a pit viper snakebite (Agkistrodon halys brevicaudus)

Snake venom can cause myriad local and systemic signs and symptoms. Neurotoxic effects include difficulty seeing, diplopia, difficulty in opening the mouth, speaking, or swallowing, and difficulty getting out of bed the morning after the snakebite. Because of the unique structure of the extraocular muscles, they are particularly susceptible to the neurotoxin. Rarely, though, are symptoms of snakebite confined to the extraocular muscles. This case report describes a patient who experienced only extraocular manifestations of envenomation. It is important for clinicians to recognize this unique neurotoxic manifestation and to begin treatment of snakebites, because delay in treatment could cause permanent injury and even death.