An adder bite can be fatal for dogs. Here's what to do if it happens

The adder is the only venomous snake in the UK and while bites usually don't cause problems they can be life-threatening for dogs.

Adders tend to keep themselves to themselves and don't bite unless they are scared, says PDSA Vet Emma Fisher.

Sometimes, however, dogs become curious and start sniffing, stepping near, or even pouncing at them — all of which can startle the adder and provoke a defensive strike. Generally, most bites happen between the months of April to September, but they are especially common between June and August. 

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Most adder bites are not life-threatening, and with prompt treatment, most dogs make a full recovery.  

However, the severity of symptoms can vary depending on factors such as the size of your dog, where on their body the bite occurs, the amount of venom injected, and whether the venom reaches and spreads through the bloodstream.

If the bite is mild and the venom stays in the tissues around the bite, it may only cause pain and swelling, and intensive treatment might not be necessary. That said, it’s still absolutely crucial to contact your vet immediately for guidance if you suspect an adder bite – early treatment can make a big difference if it’s needed. 

The bite becomes much more serious if the venom enters the bloodstream, potentially causing symptoms like fever, lethargy, collapse, and, in severe cases, seizures, clotting issues, organ failure, or even death. Bites to the face or neck can also be particularly dangerous due to the risk of swelling blocking the airways. For any suspected adder bite, contact your vet immediately to assess the situation and ensure your dog gets the proper care. 

What to do if your dog is bitten by an adder

1. Stay calm. 
2. If you see the snake, try to remember what it looks like, or take a photo from a distance. Do not try to find the snake, get close to it, touch it or harm it. (Adders are a protected species so it is illegal to hurt or kill them, and they can bite people if disturbed.)
3. Keep your dog as still as possible to prevent venom spreading around their body. 
4. Leave the bite alone - don't apply a bandage or tourniquet. 
5. Call your vet to let them know you are coming down to the practice. 
6. If possible, bring your car to your dog or depending on their weight, carry them to it. 

What do adders look like?

Adders are easy to identify, they are small, grey/brown snakes with a distinctive V-shaped marking on their head and dark zigzag pattern down their back. 

They are most common in long grass, woodland, moorland and by the coast (sand dunes/coastal paths). They are generally active through the months of February to October and hibernate during the winter. 

What are the symptoms of an adder bite?

Adder bite symptoms can take anywhere between couple of minutes to an hour to develop. They tend to be worse in dogs that are bitten on the face or neck, and much worse if the venom makes its way into the blood stream. 

Mild symptoms:

• Pain and swelling around the bite 
• Limping (if bitten on a leg) 
• A few tiny bite marks 

Serious symptoms:

• Vomiting and diarrhoea
• Pale gums 
• Panting 
• Drooling 

Very severe and potentially life-threatening symptoms:

• Weakness and wobbling 
• Swelling to the face or neck 
• Severe bruising and abnormal bleeding 
• Tremors and seizures
• Difficulty breathing
• Collapse
• Sudden death can occur if adder venom is injected straight into the blood stream 

Treatment

If your dog has been bitten by a snake, it’s important they are seen by a vet as soon as possible, don’t attempt to treat them at home or wait for symptoms to show. Treatment will depend on the symptoms they develop, but as a start, is likely to involve: 

• Strong pain relief
• Careful monitoring - your vet will monitor your dog closely and keep an eye out for complications such as kidney failure, heart problems and bleeding problems. It’s likely that your dog will need to stay in for monitoring and investigations (such as ECG’s and blood tests) for at least 24 hours unless they only have very mild symptoms. 
• A fluid drip - to support their blood pressure and keep bloodflow going to internal organs (such as the liver, kidneys and heart) if they have gone into shock. 
• Antihistamines - to help reduce swelling and further symptoms developing. 

In more serious cases, your dog might require: 

• Anti-venom - anti-venom is sometimes necessary in more severe cases, however, there is a small risk of a drug reaction when using anti-venom, and it can be difficult to get hold of. 
• Antibiotics - only necessary if your dog develops an infection around their bite wound 
• Surgery - some dogs develop necrosis (tissue death) around the bite wound. If your dog develops necrosis, they may need an operation to remove the dead tissue. 

When to contact your vet

Snakebites should always be treated as an emergency - if your dog has been bitten, follow PDSA’s first aid advice and call your vet straight away. Do not attempt to treat your dog at home.

How can I prevent an adder bite

There are few steps you can take to help prevent your dog being bitten by an adder: 

• Avoid areas well known for adders in the warmer months (especially April-September) or when in those areas, keep your dog on a path and on a lead. 
• If you are holiday somewhere you aren’t familiar with, do some research to find out if there are any adder ‘hot-spots’ before walking your dog. 
• Remember, adders are most commonly found in long grass, woodland, moorland, and along the coast (sand dunes/coastal paths). 

Cost

Treating an adder bite can be very expensive, especially if your dog needs intensive care in a veterinary hospital. It’s important to speak openly to your vet about your finances, the cost of treatment, as well as what you think is right for your dog. 

When you welcome a new dog into your life, consider getting dog insurance straight away before any signs of illness start. This will give you peace of mind that you have some financial support if they ever get sick.  

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