Dog healthFeverMedicines

Dog fever: what to do, and what never to give

A fever in a dog is a reason to see a vet, not to give Dolo, Crocin or Combiflam, which can poison dogs. What to do instead, and the signs that mean go now.

··9 min readEditorial

A fever in a dog is a reason to see a vet, not to give a tablet. Human fever and pain tablets such as Dolo 650, Crocin and Combiflam can poison a dog, and a fever needs its cause found. Phone your vet, and go to a veterinary hospital at once if the temperature is above 40 °C (104 °F) or your dog has trouble breathing or severe bleeding.

What should I do if my dog has a fever?

Phone your vet. The Merck Veterinary Manual says emergency care often starts with a phone call to the veterinarian, and that calling ahead helps the clinic prepare for your arrival.

Go to the nearest veterinary hospital now if any of these is true.

  • The temperature is above 40 °C (104 °F) or below 37.2 °C (99 °F). VCA Animal Hospitals calls both of these emergency situations.
  • Your dog has trouble breathing, severe pain, or severe or uncontrolled bleeding. These are on the Merck Veterinary Manual’s list of emergencies requiring immediate veterinary care.
  • Your dog may have swallowed a human medicine. Poisoning is on the same Merck list. The ASPCA says not to wait for the signs to worsen before getting help, and to take any packaging with you. For seizures, trouble breathing or no response, it advises the nearest veterinary hospital immediately.

Tell your vet at once if you also see nosebleeds, blood in the urine or faeces, easy bruising, poor coordination, weakness or partial paralysis. Merck lists these among the signs of long-term ehrlichiosis, a tick-borne disease that causes fever.

Tell your vet what you know. VCA says it is important to tell your veterinarian about any recent travel or boarding, exposure to unknown or infected animals, exposure to fleas or ticks, recent vaccinations, and any supplements or medications. Add the temperature and when the fever began.

Do not give Dolo, Crocin, Combiflam, Brufen, Voveran or Disprin while you wait. The reasons are below, and our page Human medicines that are dangerous to pets lists what is in each brand. If your dog has already swallowed one, do not try to make it vomit: the ASPCA says doing so at home can be dangerous, and that it should only be done under the guidance of a veterinary professional.

What is a normal temperature for a dog?

The Merck Veterinary Manual’s table of normal rectal temperatures gives 37.5 to 39.2 °C (99.5 to 102.5 °F) for dogs and 38.1 to 39.2 °C (100.5 to 102.5 °F) for cats. Other veterinary pages give slightly different lower limits, so ask your vet about a reading near the bottom of the range.

VCA adds that some pets maintain a baseline temperature a little above or below average. It says that fever refers to an elevated body temperature, and it names temperatures above 40 °C (104 °F) or below 37.2 °C (99 °F) as emergency situations.

A reading can be wrong. VCA says falsely elevated temperatures occur when pets are over-excited or agitated, and advises letting the pet rest for 10 minutes, calming it down, and trying again. If the temperature remains high or low, VCA says to see your veterinarian.

How do I take my dog’s temperature?

You do not need a reading to phone the vet, and you should not delay the call to get one. If you want one to report, VCA says that taking a pet’s temperature may be a two-person task and gives these steps for a rectal reading.

  • Use a digital thermometer. VCA says a digital thermometer normally used under a person’s tongue can be used rectally in a pet. It does not recommend glass thermometers, because they are easy to break and exposure to mercury is hazardous.
  • Lie the dog down on its side. VCA says that if you insert a rectal thermometer while a pet is standing, it will likely sit down on the thermometer.
  • Lubricate the tip with petroleum jelly. Insert the thermometer until the metal tip is completely in the rectum, and hold the end to steady it and make retraction easier.
  • If you feel stool, try to place the thermometer around it rather than through it.
  • If the dog clamps its anal sphincter, do not force the thermometer into the rectum, to avoid injury and pain. If it is too difficult, VCA advises letting trained professionals take the temperature at your veterinary hospital.

VCA also describes digital ear thermometers. It says their readings are reasonably accurate but not always precise, and that using one on a dog with an ear infection will produce slightly inaccurate readings.

Why can’t I give my dog Dolo, Crocin or Combiflam?

Because they can poison a dog, and because a fever needs its cause found. The brands below were checked against the manufacturer’s leaflet or an Indian pharmacy listing in October 2026. Read the ingredient list on your own pack, because formulations change.

  • Dolo 650 (Micro Labs): paracetamol
  • Crocin 650: paracetamol
  • Calpol (GSK): paracetamol
  • Combiflam (Sanofi): ibuprofen and paracetamol
  • Brufen (Abbott): ibuprofen
  • Voveran (Novartis): diclofenac
  • Disprin (Reckitt): aspirin

Paracetamol. Pet Poison Helpline says that while paracetamol is safe for human use, it has a narrower margin of safety in dogs and is especially dangerous for cats. It lists gastrointestinal distress, blood abnormalities and liver failure among the signs. The Merck Veterinary Manual says jaundice, liver injury and necrosis are more common with paracetamol poisoning in dogs than in cats, and lists loss of appetite, belly pain, vomiting, lethargy and trembling as other signs. It also notes that poisoning can occur at lower doses with repeated exposure. For cats the danger is even greater: see Why paracetamol (Dolo, Crocin, Calpol) is dangerous for cats.

Ibuprofen, diclofenac and other anti-inflammatory painkillers. Pet Poison Helpline names ibuprofen, naproxen sodium and diclofenac as common human NSAIDs. It says that when they are ingested in toxic amounts they can cause severe stomach ulceration and acute kidney failure in dogs, and that any type of NSAID should never be given to a dog or cat without consulting a vet. The signs it lists include vomiting, diarrhoea, bloody vomit, black tarry stool, loss of appetite and lethargy.

Aspirin. Merck lists listlessness, weakness, loss of appetite, and vomiting with or without blood among the signs of aspirin poisoning.

They do not treat the cause. VCA says anti-inflammatory drugs for the most part do not treat the fever itself and should be withheld until diagnostic tests are completed. Combiflam’s own prescribing information, written for people, says the tablets “can mask symptoms of infection, which may lead to delayed initiation of appropriate treatment”. The same document lists an existing stomach or intestinal ulcer or bleeding, and kidney or cardiac failure, among the conditions in which it should not be used.

A dose cannot be looked up. Pet Poison Helpline lists a number of factors, such as the amount ingested, the size of the animal and allergies, that affect what is toxic to a particular pet. We do not give a dose for any medicine, and we do not call any amount safe.

What causes a fever in dogs, and what will the vet do?

VCA lists the causes: a viral, bacterial, fungal or parasitic infection in any body system, inflammation from an immune-mediated problem, a reaction to a drug or vaccination, and an underlying cancer. VCA says most dogs with a fever are lethargic, reluctant to move and have a loss of appetite. It also lists increased heart and breathing rates, dehydration, shivering and stiffness.

Ticks are one cause to raise with your vet. Merck says the bacteria that cause ehrlichiosis are spread by ticks, such as the brown dog tick, lone star tick and black-legged tick. In the early stage, common signs include fever, swollen lymph nodes, an enlarged spleen and a low blood platelet count. Merck says most short-term cases happen during warmer months when ticks are more active, that diagnosis is made with blood tests, and that treatment is usually a course of antibiotics.

VCA says that for a dog with a fever the vet will perform a thorough physical examination. Blood tests usually include a complete blood cell count, a serum biochemistry panel and a urinalysis, and further tests, such as X-rays or ultrasound, may be recommended. VCA says antibiotics are often prescribed for an underlying bacterial infection, but that ideally, if they are used, diagnostic testing is done before they are started.

This article is general education. It is not veterinary advice and cannot examine your dog. See our disclaimer and editorial policy.

Frequently asked questions

Can I give my dog paracetamol (Dolo or Crocin) for a fever?

No. Dolo 650 and Crocin are paracetamol, which Pet Poison Helpline says, while safe for human use, has a narrower margin of safety in dogs. Phone your vet instead.

What temperature is a fever in a dog?

VCA defines fever as an elevated body temperature, and the Merck Veterinary Manual’s table gives 37.5 to 39.2 °C as the normal rectal range for dogs. VCA calls a temperature above 40 °C (104 °F) an emergency.

What are the signs of a fever in a dog?

VCA says most dogs with a fever are lethargic, reluctant to move and have a loss of appetite. It also lists increased heart and breathing rates, dehydration, shivering and stiffness.

Can a tick bite cause a fever in a dog?

Yes. Merck says ehrlichiosis is spread by ticks such as the brown dog tick, and lists fever among the common signs in the early stage. VCA asks owners to tell the vet about any exposure to fleas or ticks.

Sources

General education, not veterinary advice for your animal. See the disclaimer and how articles are checked in the editorial policy.

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