Correct treatment of adder bites can reduce morbidity. We aim at creating an evidence-based guideline on pre- and in-hospital treatment of bites by the European adder (Vipera berus). Pre-hospital treatment consists of reassurance, immobilisation, elevation and paracetamol for pain. Icepacks, oral suction and tourniquets should be avoided. In-hospital treatment includes tetanus prophylaxis, paracetamol or opioids, antiemetics and the monovalent ovine immunoglobulin Fab fragment ViperaTAb. We strongly advise emergency departments to carry up-to-date guidelines regarding bites from the European adder.