Snake Antivenom

Antivenom is a medicine that is given to stop snake venom from causing serious blood, tissue, or nervous system problems. Side effects from antivenom can include a rash, itching, swelling, and body aches.

The use of antivenom depends on how much venom was injected (envenomation) and the type and size of the snake. Large snakes tend to inject more venom than smaller snakes do. Antivenom is used for mild, moderate, and severe envenomations.

  • Dry bites (no venom injected) do not need to be treated with antivenom.
  • Mild envenomation bites may cause mild symptoms, such as mild bleeding, pain, and swelling at the bite.
  • Moderate envenomations are more likely to cause symptoms of severe pain, swelling of the whole limb, nausea, vomiting, and weakness.
  • Severe envenomation symptoms include severe pain, severe swelling, trouble breathing, moderate to severe bleeding, severe allergic reactions, and signs of shock.

Antivenom should be given as soon as possible after the bite. It is usually given within the first 4 to 6 hours after the snakebite and may be effective for 2 weeks or more after the bite.

Serum sickness is a delayed reaction to receiving antivenom and can occur several days or weeks after treatment. Symptoms of serum sickness include a fever, a rash, hives, and joint aches. Contact your doctor if you have received antivenom medicine and you now have symptoms of serum sickness.

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Current as of: October 1, 2025

Author: Ignite Healthwise, LLC Staff
Clinical Review Board
All Ignite Healthwise, LLC education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: October 1, 2025

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Ignite Healthwise, LLC education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.