In many cases, the venom has also entered the lymphatic system, so cutting off the blood supply would do little more than harm the injured tissue, possibly leading to necrosis. Tourniquets are typically used to control severe bleeding, and even so, they must be loosened slightly periodically to try and lessen the possibility of gangrene. The best thing to do is call 911 and try to keep the victim calm until help arrives. Most major medical facilities should have antivenin on hand for snakes indigenous to the area.

Sucking out venom, either by mouth or with a pump, does not work and may harm the affected area directly. Suction started after 3 minutes removes a clinically insignificant quantity—less than one thousandth of the venom injected—as shown in a human study. In a study with pigs, suction not only caused no improvement but led to necrosis in the suctioned area. Suctioning by mouth presents a risk of further poisoning through the mouth’s mucous tissues. The well-meaning family member or friend may also release bacteria into the victim’s wound, leading to infection.