A fever in a dog can be a sign of infection or other illness. However, a high body temperature can also be caused by overheating, and it's important to distinguish between these conditions. Take the dog's temperature if you can safely do so, and always consider how your dog is feeling – not just the number on the thermometer.
Does your dog have a high temperature and seem clearly ill? Call your veterinarian immediately if your dog has a temperature of 40°C or more at rest, or if your dog has difficulty breathing, collapses, has convulsions or is difficult to contact – regardless of the temperature. A temperature of 41°C or higher requires emergency care. If heatstroke is suspected: start cooling with water immediately and contact your veterinarian at the same time. Do not give Paracetamol, Ibuprofen or other human medications without the veterinarian's permission. Call 33 13 98 40 for emergency care at A-VetOutside opening hours: contact the veterinary on duty.
What is a normal temperature for a dog?
In adult dogs, the rectal temperature is usually around 38–39,2 °C. The normal value varies somewhat between individuals and with activity and stress. It can be useful to know your dog's temperature when it is healthy and relaxed. See also veterinary normal values for dogs.
A temperature above about 39,2°C is elevated, but one measurement alone does not indicate whether the dog has a fever. If repeated measurements around 39,5°C or higher at rest are observed, you should contact your veterinarian the same day. Also contact your veterinarian at lower temperatures if your dog appears ill.
Activity and stress can temporarily increase the temperature. Allow an otherwise unaffected dog to rest quietly before taking another measurement. Do not use this as a reason to wait if the dog seems unwell, has been exposed to heat or has other danger signs.
What is the difference between fever and overheating?
In the case of a fever, the body's temperature regulation is set to a higher level, for example as part of an inflammatory reaction. In the case of overheating, the body produces or absorbs more heat than it can get rid of, without the temperature regulation having set a higher target. Fever and overheating therefore require different management. Read the veterinary explanation of fever.
Heat stroke is a serious heat-related condition. It can occur during physical activity, in a hot car, or in other hot environments—not just in direct sunlight. A slightly elevated temperature after activity is not automatically heat stroke, but severe panting, weakness, or collapse after heat or activity should be taken seriously.
When should you contact a veterinarian?
- Call immediately: Temperature of 40°C or more at rest, or rapid deterioration. At around 41°C or higher, the dog needs emergency help.
- Call immediately regardless of temperature: Difficulty breathing, collapse, convulsions, obvious confusion, decreased consciousness or pale/white gums. A suddenly swollen or painful abdomen also requires prompt evaluation, especially if vomiting occurs without anything coming up. The same applies to suspected heatstroke or poisoning.
- Contact a veterinarian the same day: Repeatedly elevated temperature at rest, especially around 39,5°C or higher, or temperature rise together with lethargy, poor appetite, vomiting or diarrhea.
Temperature limits are practical guides, not boundaries between healthy and sick. Normal temperature does not rule out serious illness. Have a low threshold for calling in case of illness in puppies, older dogs, and dogs with known illness. Veterinary guidance on temperature measurement.
Puppies with signs of illness
Contact your veterinarian immediately if a puppy has an elevated temperature or appears ill. Lethargy, poor appetite, vomiting, or diarrhea should not be ignored until the temperature reaches a certain limit. The normal range for adult dogs does not automatically apply to newborn puppies.
Be aware of post-menstrual uterine inflammation
In an unspayed female dog, lethargy, increased drinking, vomiting, discharge, or a tender or swollen abdomen may be signs of uterine inflammation, especially in the weeks following the season. Call your veterinarian immediately if you suspect this. Neither fever, discharge nor a visibly swollen abdomen need be present. The condition can be life-threatening and is usually treated with surgery after stabilization. Veterinary source: uterine inflammation.
What symptoms can accompany fever in dogs?
- lethargy and less interest in activity
- decreased appetite
- Shivering or the dog seeking warmth
- faster breathing or panting
- changed desire to drink
These signs can have many causes. Vomiting, diarrhea, coughing, or pain can give your vet information about what is causing them. Also tell them about any new medications, recent vaccinations, travel, tick bites, or possible exposure to toxic substances.
A dry or warm muzzle, warm ears, and warm paws cannot be used to determine if a dog has a fever. The temperature must be taken.
How do you measure your dog's temperature?
A digital rectal thermometer is a practical choice for at home. Use one with a flexible tip and clearly label it for use only with your dog.
- Let the dog stand or lie still. It is often easier if another person helps to hold it gently.
- Lubricate the thermometer tip with a little water-based lubricant or petroleum jelly.
- Gently lift the tail and gently insert the lubricated tip into the rectum. Follow the thermometer's instructions; the depth of insertion required depends on the thermometer and the size of the dog. Do not use force.
- Hold the thermometer steady until the measurement is complete. Remove it and note the temperature and time.
- Clean the thermometer according to the manufacturer's instructions.
Stop if the dog shows pain or resists strongly. Have your vet measure if you are unsure. Do not delay emergency care to have your temperature taken.
What can cause fever?
Fever can be caused by infections, immune-mediated inflammatory diseases, some cancers or reactions to drugs. Some dogs experience a temporary increase in temperature after vaccination. In the event of persistent fever or decreased general condition, the cause must be evaluated by a veterinarian.
Stress, strenuous activity and heat can also increase body temperature, but this is not necessarily a fever. Information about what the dog was doing before the temperature was measured is therefore important.
What can you do at home while you wait for advice?
Let your dog rest in a comfortable, well-ventilated room and have fresh water available. Do not force food or water on him. Avoid exercise and monitor his breathing, alertness and ability to drink. Record temperature readings and other symptoms for your veterinarian.
Do not attempt to treat a common fever with a cold bath on your own. Active cooling is first aid for overheating, not general advice for all dogs with a fever.
If heatstroke is suspected
Move the dog out of the heat, stop the activity and start cooling immediately. Moisten the body with plenty of cool water and provide air movement, for example with a fan or air conditioner. Keep water away from the nose and mouth, especially if the dog is drenched. Do not wrap the dog in wet towels.
Contact your veterinarian at the same time and arrange for rapid transport. Start cooling before departure, and if possible continue en route according to your veterinarian's advice. Do not wait for your dog to become completely normal. He needs assessment even if his temperature drops and he seems better. Read more about heatstroke in dogsThe cooling recommendations are based on Royal Veterinary College recommendations.
Can the dog be given Paracetamol or Ibuprofen?
Do not give fever-reducing or pain-relieving medications to people on your own initiative. Ibuprofen and paracetamol can cause serious poisoning. Your veterinarian must decide which drug and what dose is appropriate. Read the FDA's advice on painkillers for animals.
If your dog has ingested such medications, call your veterinarian immediately and state the medication, strength, possible amount, time of administration, and the dog's weight. Do not wait for symptoms. Read more about poisoning in dogs.
Examination at A-Vet Small Animal Clinic
The veterinarian will assess the general condition, medical history and temperature along with a clinical examination. Blood tests, urine tests or imaging tests may be necessary, depending on the findings. Treatment is directed at the cause; antibiotics are not necessary in all cases of fever.
