Snakebite and Venomous Injuries

Key points

• • The medically important venomous snakes in India are the cobra and krait (mainly neurotoxic) and the Russell's viper and saw-scaled viper (mainly vasculotoxic), though venoms often have mixed effects.
• • Neurotoxic venom blocks transmission at the neuromuscular junction, causing drooping eyelids (ptosis), difficulty in swallowing and paralysis of the breathing muscles.
• • Viper venom is mainly vasculotoxic, disturbing clotting and damaging vessels to cause bleeding, local swelling, blistering and tissue death, though some vipers also have other effects.
• • Krait bites are often painless and may happen during sleep, so the diagnosis can be missed until paralysis appears.
• • In forensic work, fang marks, the pattern of poisoning and detection of venom help distinguish a snakebite death from other causes.