Yearly, about 250-300 patients are treated at hospitals in Sweden after bites from the adder, Vipera berus, the only domestic venomous snake in Sweden. Moderate or serious symptoms occur in 20-30% of those patients. Sometimes no symptoms occur, which depends on if the snake has injected venom or not.

Adder bites often results in severe local pain and progressive swelling and a bluish discoloration. In serious cases early general symptoms might include dizziness, nausea, vomiting, diarrhea, abdominal pain, difficulty breathing, hypotension, cardiac disturbances, impaired consciousness.

In case of adder bite

• Keep the person calm and at rest with the bitten body part preferably elevated.
• Call the Poison Centre or a doctor for advise.
• All persons with an adder bite should obtain medical attention.
• A person with progressive general symptoms must seek medical attention immediately. Call 112 for an ambulance.