If you’re like many people, one of the first things you do when you experience chills, unexpected sweats, or a feeling of illness is to take your temperature. Taking your temperature allows you to determine whether or not you have a fever. It can even help diagnose low body temperature or hypothermia if you have recently come in from an outing in the cold.
Checking your dog’s temperature can offer the same benefits. If your dog appears unwell and you’re concerned about hypothermia, fever, or heatstroke, taking your dog’s temperature is a simple way to gain information that can help you decide what to do next.
In order for this information to be useful, though, you need to know what constitutes a normal dog temperature and how to take your dog’s temperature accurately.
What’s a Normal Dog Temperature?
An average dog temperature ranges from 99.5-102.5 degrees Fahrenheit. Your dog’s temperature may fall slightly outside of that range for brief periods of time (if your dog is exposed to cold outdoor temperatures or has been exercising in warm weather), but any significant departure from that range is cause for concern.
A temperature below 98 degrees indicates that your dog likely has hypothermia, while a temperature above 102.5 degrees could indicate a fever or heat stress.
What Body Temperatures Are Unsafe for Dogs?
Hypothermia in dogs refers to a body temperature below 98 degrees. This can occur when a dog is exposed to cold outdoor temperatures, or when a dog’s internal temperature regulatory mechanisms are not working properly due to illness or injury.
Environmental temperatures below 45 degrees can cause hypothermia in dogs, depending on their breed, size, age, degree of cold-weather acclimation, and other environmental factors (such as the presence of rain or wind). Hypothermia is more common in small-breed dogs, young puppies, elderly dogs, and dogs with underlying health issues. Early signs of hypothermia include shivering and body parts that are cold to the touch, while signs of severe hypothermia include collapse and unresponsiveness.
Hyperthermia, or elevated body temperature, refers to a temperature above 102.5 degrees in a dog. There are a number of factors that can cause an elevated body temperature. One possibility is a fever, which is the body’s normal response to inflammation or infection.
Additionally, exercise in a warm environment can lead to an elevation in temperature. Some dogs even develop a slightly elevated body temperature when they are very stressed or excited. For this reason, if your dog’s temperature is slightly elevated at a veterinary visit, your veterinarian may give your dog time to settle down and retake your dog’s temperature later in the visit.
A persistently elevated temperature suggests a fever, while a temperature that comes back down once your dog is calm suggests that the temperature increase was due to excitement.
Heatstroke in dogs is defined as a temperature above 104 degrees. This can occur if a dog is locked in a car or left outside on a hot summer day. Dogs vary significantly in their susceptibility to heatstroke. Brachycephalic breeds (like English Bulldogs) can even experience heatstroke at temperatures that many humans would consider comfortable, because their respiratory abnormalities limit their ability to cool themselves effectively through panting.
Early signs of heat stress in dogs include increased panting and dark red mucous membranes (gums and tongue). In later stages, dogs may collapse and become unresponsive.
How to Tell if Your Dog Has a Fever
The only effective way to determine whether a dog has a fever is to take your dog’s temperature, using a dog thermometer.
A dog that feels warm to the touch does not necessarily have a fever, nor should you panic if your dog’s ears are hot, because a normal dog temperature is consistently higher than a human’s body temperature. More reliable dog fever symptoms include lethargy, decreased appetite, increased panting, and shivering.
Many people worry that a warm nose indicates a fever. This is a myth. Your dog’s nose will always feel warm to the touch, unless your dog has recently licked their nose and moistened it. Most dogs lick their nose often, which is why we expect a dog’s nose to feel cold. If your dog’s nose is warm, it just means that they haven’t licked their nose recently.
How to Take a Dog’s Temperature
The best way to take your dog’s temperature is rectally, using a fast-reading digital thermometer. Coat the thermometer with a thin layer of lubricant (such as petroleum jelly) and insert the thermometer approximately one inch into your dog’s anus.
It’s best to do this with help from an assistant, who can hold your dog still and distract them with treats or cuddles. Some dogs do not like having their temperature taken, so be careful that your dog does not bite anyone during this process!
If your dog will not tolerate having their temperature checked rectally, you can use an aural (ear) thermometer. Unfortunately, these thermometers are less accurate than rectal thermometers. Still, an ear temperature can be helpful if you are unsure whether your dog’s temperature is normal.
When to Visit a Veterinarian
A normal dog temperature ranges from 99.5-102.5 degrees. If your dog’s temperature is within this range, you don’t need to be concerned or seek veterinary care unless your dog is showing other signs of illness.
If your dog’s temperature is within one degree of the normal range and they are otherwise acting normal, wait an hour or two and then retake your dog’s temperature. A persistent, reproducible low or elevated temperature warrants a call to your veterinarian, but a temperature is just a snapshot in time and it’s not uncommon to obtain a normal reading when you recheck your dog’s temperature.
If your dog’s temperature is below 98 degrees or above 103.5 degrees, you should seek veterinary care as soon as possible. Contact your veterinarian (or an emergency veterinarian, if your veterinarian is closed) for guidance.
Remember that your dog’s temperature is only one piece of information. If your dog is acting completely happy and healthy, with a normal attitude, appetite, and energy level, you probably do not need to be too concerned unless their temperature is below 98 degrees or above 103.5 degrees.
Similarly, if your dog is acting visibly ill (lethargic, not eating, vomiting, having diarrhea, etc.), you should seek veterinary care even if your dog’s temperature is normal.