A blue rescue inhaler sits on top of a glass table.
If your dog chews on an asthma inhaler like this one, your pet may develop life-threatening symptoms due to salbutamol, an asthma drug. Photo: Ava Arends.

Asthma inhalers: lifesaving for us, but life threatening to our pets

Blue rescue inhalers containing an airway-opening drug called salbutamol are lifesavers for people with asthma, but these medical devices pose a life-threatening risk to pets.

By Ava Arends

One out of every 10 Canadians lives with asthma, a chronic lung condition that inflames and narrows the airways in the lungs. Since the disease is so prevalent in humans of all ages, the blue rescue inhaler (also described as “blue reliever inhalers”) has become a familiar item found on the tables or counters of many households.

While asthma patients need ready access to the medication, the devices can release potentially lethal dosages of the asthma drug to a curious pet that likes to chew.

When a “dog punctures the asthma inhaler, they get … presumably all of the drug [remaining in the canister] because it's pressurized,” says Dr. Vanessa Cowan, a veterinarian and toxicologist at the Western College of Veterinary Medicine (WCVM).

She stresses that this scenario is a health emergency for your dog: “If you find a chewed inhaler in your household … it’s imperative that a dog be taken to the hospital right away because they received so much of the drug in such a short period of time.”

According to the American Society for Prevention of Cruelty to Animals (SPCA), human medications are the most common toxin ingested by pets. Among human prescription medication toxicoses seen at the WCVM’s Veterinary Medical Centre (VMC), salbutamol stands out as an important one for both owners and veterinary staff to be aware of due to the potential lethal dosages received when dogs chew on the pressurized metered-dose inhalers.

Cowan’s research team at the WCVM is examining past cases of salbutamol toxicoses that have occurred at the college’s teaching hospital to better understand how these cases present and progress, and the subsequent outcomes of patients.

Salbutamol (also known as albuterol in the United States) can be prescribed in multiple forms including tablets, syrups, powders or aerosols, but inhalers are the most common way that the drug is delivered to human patients. As Cowan points out, “salbutamol is excellent [at the prescribed dose] for treating asthma symptoms when people have chest constriction.”

But when the metered-dose inhalers are punctured by curious dogs, they deliver the drug at inappropriate doses, which may cause severe clinical signs, including:

  • rapid heart rate (tachycardia)
  • electrolyte imbalances such as low potassium (hypokalemia) and low phosphate (hypophosphatemia)
  • cardiac arrhythmias

These side effects have a rapid onset and can occur as quickly as 30 minutes after exposure, and they can even be lethal in some pets if not addressed quickly.

“Regardless of … [whether] the inhaler is believed to be full or nearly empty, the dog should be taken to a veterinarian,” stresses Cowan.

She warns that with cases of salbutamol overdosing, there can be abnormal “electrolyte [levels] in the bloodstream … [which] put [our pets] at risk for cardiac arrhythmia.”

Veterinarians can monitor a pet’s heart rate, blood pressure and electrolyte levels, and they can perform an electrocardiogram to ensure the heart is functioning normally. Without this type of clinical assessment and treatment, potential issues can go unnoticed and can lead to long-lasting cardiac injuries.

Fortunately, with proper monitoring and treatment, dogs that have punctured a salbutamol canister have a good prognosis.

“Dogs tend to get into things that they shouldn't, and salbutamol is a perfect example of that,” says Cowan, who recommends that people store their asthma inhalers well away from their pets’ reach.

“This includes any sort of asthma inhalers that are prescribed for pets, [as] asthma is a condition that occurs in animals [too],” says Cowan.

Pet owners who have asthma inhalers in their homes can also watch for symptoms of poisoning in their animals that may include:

  • hyperactivity or agitation
  • tremors
  • respiratory distress, such as rapid breathing (tachypnea)
  • gastrointestinal signs, specifically vomiting
  • weakness and lethargy and potential paralysis

Cowan says there’s a general lack of awareness about the dangers of pressurized metered-dose inhaler canisters, which is why owner education about this issue is very important.

“Oftentimes, owners are just not aware of the risk to the pets, which is no fault of the owner,” says Cowan. “You don't expect that your dog is going to take your medication and chew on it — but it happens.”

Veterinarians can help spread the word by ensuring their clients know the risks and are aware that they must take their pet to an emergency veterinarian when these poisonings occur. With more awareness about the risks, Cowan hopes the number of salbutamol toxicosis cases that veterinarians see every year will be reduced.

Emergency poison information for animals: in the event of a suspected poisoning, contact your local veterinarian or call 1-855-764-7661 (Pet Poison Helpline, available throughout North America; an incident fee applies).

Ava Arends of Kamloops, B.C., is a second-year WCVM veterinary student who worked as a summer research student in 2025 with financial support from the college’s Interprovincial Undergraduate Summer Research program. Her story is part of a series of science news articles written by WCVM summer research students.

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