12/06/2025
Adders are the only venomous snake in the UK and are most seen from spring to summer in open habitats such as sand dunes, heathland, moorland, and woodland.
They are usually grey or brown in colour with a dark distinctive zig-zag pattern down their back. Although they are not aggressive, they will strike when agitated or startled and their venom is toxic to animals.
Swelling around the site is usually seen within two hours, and two puncture wounds may be visible in the centre of the swelling. You may notice signs of lameness, bleeding, and bruising. Once the venom has absorbed into the body, a widespread inflammatory response is triggered which may lead to:
🐍Lethargy
🐍Vomiting/diarrhoea
🐍Pale gums
🐍Increased respiratory and heart rate
🐍Increased salivation
In severe and untreated cases of adder bites, dogs can experience muscle tremors or convulsions, collapse, coagulopathy (blood clotting problems), and organ failure. The seriousness of a bite is influenced by the dog's size, the bite's location, the volume and potency of venom injected, and the duration and extent of movement following the bite.
It is important to note that not all adder strikes result in venom injection; these are known as "dry bites." However, even dry bites can lead to pain, swelling, and infection. Since it is not immediately apparent whether a bite is venomous or dry, it is crucial to contact a vet immediately. Providing advance notice of your arrival allows the vet to prepare, potentially sourcing antivenom from another facility, or redirect you if necessary.
There is a high rate of survival, even in severe instances, provided that treatment is administered quickly. Treatment typically involves managing shock, providing pain relief, and in some situations, administering an intravenous antivenom that neutralizes the venom.
To prevent bites in areas with known adder populations, dogs should be kept on a lead and confined to footpaths. Adders are a protected species in the UK under the Wildlife and Countryside Act, 1981, and it is illegal to harm them.
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