Is Malignant Hyperthermia A Common Condition In Dogs? How To Keep Your Fur Baby Cool And Calm

Is Malignant Hyperthermia A Common Condition In Dogs?

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Malignant hyperthermia is a condition that occurs when there is a rise in body temperature. The elevated temperature causes an increase in acidity in the blood, which results in muscle damage and death.

Malignant hyperthermia, also called MH or methemoglobinemia, is a syndrome that affects dogs and can be fatal. The condition occurs when dogs experience an abnormal rise in body temperature due to an increase in metabolic rate caused by genetic mutations. 

A dog with a body temperature of 103? ae considered hyperthermic. This can occur even if your dog does not appear hot, as it is not about his core body temperature but rather his sweat rate.

Malignant hyperthermia is a genetic condition. It's rare in dogs, but it can happen. It is generally caused by a change in how the body reacts to certain drugs, pet medications, anesthetics, or sedatives like Acepromazine. But it can also be triggered by non–medication-related factors such as exercise or hot weather.

The signs and symptoms of malignant hyperthermia may resemble other medical conditions, including heat stroke, anxiety reaction, allergic reaction, etc. It can be treated with medication, but treatment may not always work. Dantrolene may help stop the signs and symptoms of malignant hyperthermia. 


Malignant hyperthermia is generally inherited and occurs most often in short-nosed breeds like pugs. However, it may also occur with other breeds, including German shepherds, boxers, Labrador retrievers, and Rottweilers.

The condition is inherited and occurs as an autosomal dominant trait. This means that the gene mutation is present in one copy of the chromosome and that it’s only necessary to inherit one copy of this gene to develop malignant hyperthermia. The second copy may be normal or mutated, but it doesn’t matter either because neither can produce a working protein product without the other. 

Certain Medications Can trigger Malignant Hyperthermia

A few examples of pet medications that can trigger Malignant Hyperthermia are:


Although rarer than some other genetic diseases such as hip dysplasia or elbow dysplasia, malignant hyperthermia should still be considered when you're looking for answers to why your dog has been diagnosed with heat stroke or any other type of severe overheating that doesn't seem to make sense given the circumstances surrounding your pet's condition.

So, if your dog is showing symptoms of malignant hyperthermia, it's essential to have them checked out by a veterinarian. The diagnosis will be based on your dog's symptoms and medical history. There is no laboratory test for MH susceptibility. However, the vet will perform a physical exam, check his or her heart rate and body temperature, and may run some blood tests to help pinpoint the cause of the problem. 

The Most Common Trigger

The most common triggers are anesthetics and muscle relaxants like Methocarbamol for dogs. Malignant hyperthermia is rare, but it may be just one of many ways a dog can have adverse reactions to these drugs. 

Malignant Hyperthermia Is Not Curable, But It Is Preventable

Although malignant hyperthermia is not curable, it is preventable. Following are a few ways to prevent it:

  • To begin with, dogs who have had an episode of malignant hyperthermia should never be given anesthetics again.

  • Because the condition is genetic and can be passed down from parent to offspring, breeding dogs who have been diagnosed with this condition should also be avoided.

  • Finally, since heat stress is one of the triggers for the onset of symptoms in dogs with the disorder, owners should always keep their pets calm. Some calming treats for dogs can be used, or the vets can prescribe pet medications like Adaptil or Clomicalm.


It Must Be Treated Immediately

This potentially fatal condition occurs when the body overheats and the muscles become rigid, causing a dog to breathe rapidly and pant. If your dog has been diagnosed with malignant hyperthermia, there are treatments available that can help them.

You can expect your vet to prescribe an anticholinergic drug called atipamezole or dantrolene. These medications prevent the muscles from contracting and relaxing too quickly. Another option is to try a cooling treatment similar to those used in humans suffering from heatstroke or sunburns, like placing your dog in an ice bath or wrapping them in wet towels before cold water baths at home. 

A Very Rare Disorder

Malignant hyperthermia is a rare disorder that causes your dog's body temperature to rise rapidly, causing a reaction in the neuromuscular system. Malignant hyperthermia is a rare condition that can cause a dog's body temperature to rise to dangerous levels. In fact, it's so rare that it affects an estimated 1 in 5,000 dogs.

Most cases of malignant hyperthermia will not show up until adulthood. Some puppies may develop symptoms while still nursing from their mother. However, these tend to be less severe than those seen later on in life due to their smaller size, making them more susceptible to heat exhaustion factors such as high humidity levels.

In about one-third of all cases, there isn't any known cause for this illness. However, it often occurs in combination with other inherited disorders such as dilated cardiomyopathy (DCM), mitral valve disease, and hypothyroidism. Dogs diagnosed with DCM should be tested for malignant hyperthermia if they develop an unexplained increase in heart rate during exercise or when placed under stressful conditions like surgery or anesthesia procedures. 

Recurrence And Prognosis

To prevent this condition from happening again in the future, you should avoid exposing your pet to high temperatures during exercise and hot weather conditions, especially if they've already had an episode of this condition, as well as have regular check-ups with their doctor so that any signs of a recurrence can be detected early on and treated accordingly. 


Malignant hyperthermia is a dangerous condition that can be prevented through proper medication administration. It's important for pet owners to understand the risks of certain medications and keep their dogs safe from triggers. If you suspect your dog has this condition, it's important to seek immediate medical attention from an expert in canine medicine who knows how to treat malignant hyperthermia.

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