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Animal Allergies Worse in Winter

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This information was reviewed and approved by Carah Santos, MD (12/5/2022).

DogDogs and cats may be your best friends, but, if you have allergies, they could be your worst enemy, especially in the winter. As the weather gets colder and dogs and cats spend more time inside, the level of animal dander rises in the home.

There are two major concerns:

  • It's cold, and the house is closed up.
  • There's less fresh air coming into the house.


Downside of Energy Efficiency

Because new houses are built to a high level of energy efficiency and older homes are being updated, the amount of outside air exchanged with inside air is dropping dramatically in homes throughout the United States.

Although this is energy efficient, the downside is that you're breathing the same air over and over, and allergens build up in the house, especially during the winter.

Replace Furnace Filter

A forced-air furnace also can increase problems, because it circulates dander-laden air throughout the home. Changing the furnace air filter regularly and closing the vent and door can help relieve allergy symptoms. Making a secondary filter from a piece of muslin or cheesecloth and taping it to the inside of the vent in a room also may remove some allergens.

Clean Humidifiers

Heated air also creates a considerable drop in humidity in the home, so many people use humidifiers, which can be a breeding ground for mold growth. People using humidifiers during the winter should clean them weekly with a solution of bleach and water to kill mold. Never allow humidity in the home to rise above 40 percent. At higher concentrations, dust mites, which cause allergies, begin to thrive, and the possibility of mold contamination increases dramatically.

Reduce Exposure

Evidence shows that allergy and asthma symptoms may improve over time if the recommended environmental control changes are made. Environmental control means to make changes in your environment (home, workplace, etc.) to reduce exposure to certain allergens.

Many environmental controls are for the entire home, but the bedroom is the most important, because it is where people usually spend a third to half of their time. Learn ways to reduce exposure to animal allergens even if you own a pet.

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