Smoke Season & Pets: How Wildfire Smoke Affects Dogs and Cats
As wildfires have become bigger and more severe in recent years, concerns about health effects due to their smoke are also growing.
For humans, one recent study found that hospital visits for all respiratory diseases increase by 3.3 percent on days when wildfire smoke is present, with asthma-related visits seeing a 10.3 percent increase (PMC journal article, June 2022). Another recent review mirrored this, noting that ER visits due to respiratory disease increased by 14.4 percent after wildfire smoke exposure, with asthma-related visits seeing a 57.1 increase and chronic lower respiratory disease seeing a 12.7 percent increase. Other studies further back up the respiratory health effects of wildfire smoke in humans.
But what about our companion animals? Although the research is lacking when it comes to the effects of wildfire smoke on dogs and cats, initial data points to similar effects as humans. Some veterinarians even believe our companion animals have it worse than us, since they are smaller, closer to the ground, and breathe faster than we do.
This is because the core issue when it comes to wildfire smoke is fine particulate matter, specifically PM2.5, which is small enough to penetrate deep into the respiratory tract and can cause widespread inflammation in the body. Wildfire smoke PM2.5 has also been found to contain more carbonaceous compounds than non-smoke PM2.5, making it more likely to cause inflammation and oxidative stress, according to a recent Harvard study.
What the Research Tells Us
As more dogs and cats are being brought in for emergency veterinary care following wildfire smoke exposure, more data is becoming available on the effects that this exposure is having on them.
It’s no surprise that many of these effects are similar to those experienced by humans.
“The risks of poor air quality to pets are similar to those of people, which mainly impact the heart and lungs” Dr. Aly Cohen, extension veterinarian at Cornell University College of Veterinary Medicine’s Richard P. Riney Canine Health Center, recently stated.
And although the risks are higher for specific populations of pets, veterinary hospitals such as Penn Vet’s Ryan Veterinary Hospital in Philadelphia are reporting increased breathing-related visits during days with wildfire smoke both from cats and dogs with pre-existing diseases as well as from otherwise healthy pets (American Veterinary Medical Association, May 2024).
Further Effects of Wildfire Smoke on Dogs
In addition to the documented respiratory-related issues in dogs and cats due to wildfire smoke, other data points to species-specific effects.
For dogs, this includes severe eye issues and overall oxidative stress, both of which can lead to poor health outcomes over time.
Dogs exposed to wildfire-smoke air classified as “Unhealthy for Sensitive Groups,” equating to an air quality index (AQI) of 101 to 150, had over five-times the risk of severe ocular hyperemia as did dogs in good-quality air, a 2024 study in Journal of the American Veterinary Medical Association found. This condition involves swollen or dilated blood vessels in the eye, which can lead to poor overall eye health and vision quality. The same study also found that dogs exposed to AQI 101 to 150 conditions were also at a 7,853-times increased risk of experiencing severe chemosis, or swelling of the membrane covering the eyes and inside of the eyelids.
A study on Alaska sled dogs also found that wildfire-smoke exposure led to a sharp increase in the antioxidant superoxide dismutase (SOD), indicating an oxidative-stress response (PMC journal article, August 2021).
Additional Wildfire-Smoke Effects on Cats
Wildfire smoke’s effects specifically on cats have also been studied.
In a UC Davis study on cats affected by California wildfires, more than half were found to have experienced heart muscle thickening and almost one-third (about 30 percent) had or were at risk of blood clots.
A related study found that cats living in homes with poor air quality (PM2.5 above 35 micrograms per cubic meter, or “Unhealthy for Sensitive Groups”—similar to what would be experienced in areas affected by wildfire smoke) had more than four times the likelihood of developing respiratory disease than cats living in homes with healthier air, or PM2.5 of 27.4 micrograms per cubic meter (PMC journal article, May 2018).
Keeping Your Dog or Cat Safe From Wildfire Smoke
Here are a few steps you can take to help ensure that your dog or cat stays safe from wildfire smoke.
Seek Immediate Care With These Signs
If you see these signs in your companion animal, seeking emergency veterinary care can make all the difference.
Symptoms dogs may experience due to poor air quality include the following:
- Coughing
- Gagging
- Red, watery eyes
- Fast breathing
- Difficulty breathing
- Weakness/fatigue
- Reduced appetite
- Nasal discharge
Symptoms cats may experience due to poor air quality include the following:
- Panting
- Drooling
- Sweaty paws
- Restless behavior
Even when oxygen saturation seems normal, immediate oxygen therapy is mandatory, according to a 2024 veterinary review published in Journal of the American Animal Hospital Association. The study found that pulse oximetry has proved to show falsely elevated oxygen saturation in cases of carbon monoxide intoxication.
Similarly, according to the Merck Veterinary Manual, the first treatment priority is maintenance of the airway and administration of 100 percent oxygen.
When care is prompt, survival rates are very good. One study found that, of 22 dogs and cats brought in for care within 12 hours of household fire exposure, one cat died and the other 21 animals were discharged within six days (PubMed-indexed retrospective study, October 2015).
Another study found the same, showing up to a 90 percent survival rate in cats and dogs with smoke inhalation who were hospitalized due to carbon monoxide or cyanide toxicosis or had minimal respiratory or neurologic issues in the first 24 to 72 hours (Clinician’s Brief, 2024).
Adjust Your Behavior Based on the AQI
If you weren’t familiar with AQI until reading this article, you’re not alone. A 2025 survey of dog owners found that less than one-fifth knew the AQI well, and just one-quarter checked the AQI frequently.
The U.S. Environmental Protection Agency (EPA) classifies AQI 101 to 150 as “Unhealthy for Sensitive Groups,” AQI 151 to 200 as “Unhealthy,” AQI 201 to 300 as “Very Unhealthy,” and AQI 301 and above as “Hazardous.”
When AQI is above 100, Los Angeles County Public Health advises keeping pets indoors. This recommendation is especially important for older pets and pets with heart disease or asthma.
Similar recommendations come from Oregon State University Extension, including reducing moderate to intense exercise for pets when the AQI exceeds 100, and keeping them inside except for brief bathroom breaks during air quality alerts.
When it comes to AQI, what might seem like a small difference can make a big difference for our pets. With every 1 microgram per cubic meter increase in PM2.5, there is a 1.3 increase in expected daily vet visits for cats in the “Other Unwell” category and a 1.2 percent increase for dogs (PMC journal article, 2025).
Just how much in vet bills is wildfire smoke costing pet owners? Although official figures aren’t available, researchers estimate that reducing PM2.5 to the World Health Organization (WHO) standard could save pet owners somewhere between tens and hundreds of millions of dollars per year (PMC journal article, 2025).
Keep Indoor Air Healthy
The EPA recommends that dog and cat guardians keep their animals inside as much as possible during wildfire smoke events, keeping windows and doors closed, using portable air cleaners, and avoiding particle-generating activities like vacuuming, frying, broiling, burning candles, using a fireplace, and smoking/vaping.
Be Particularly Mindful of Sensitive Groups
While even healthy animals are at risk of experiencing health risks due to smoky air, certain groups are especially vulnerable.
This includes both older and younger dogs and cats, pregnant animals, pets with heart or lung disease, and brachycephalic breeds, e.g., pugs, bulldogs, boxers, Persian cats, etc. (U.S. Environmental Protection Agency, June 2026).
Emergency Care at MyPets
If your pet is showing signs of smoke exposure, MyPets can help. Our family-owned clinic offers fast, same-day care with little or no wait time.
