Does Seasonal Affective Disorder Affect Pets?

Barri J. Morrison, DVM
By Barri J. Morrison, DVM on Jan. 29, 2024
A pet parent walks with their dog through the snow.

As winter arrives, the air gets colder and the days become shorter. This change of seasons is known to cause shifts in human behavior and mood, but it can also change your pet’s behavior.

Key Takeaways

  • There's no known scientific evidence that SAD affects pets—however, behavioral and mood changes in pets during the fall and winter months have been suggestive of SAD.
  • If you are showing signs of SAD, it’s possible your pet may show similar signs.
  • While SAD may affect your beloved companion, pain or illness can also cause mood or behavior shifts. Call your vet about any mood or behavior changes in your pet.

What Is Seasonal Affective Disorder?

Sometimes called the winter blues, seasonal affective disorder (SAD) is a type of depression related to a change of seasons. Symptoms typically begin in the fall and continue through the winter months. Most often, this change in mood resolves during the spring and summer months.

Although the exact cause of SAD is unknown, it’s suspected to be related to less sunlight exposure, which can alter sleep patterns and cause fluctuations in melatonin levels.

Melatonin is a hormone naturally produced by the brain to regulate mood and sleep-wake cycles, as well as aid in reproduction. The body produces melatonin when it is exposed to darkness and inhibits its production when it’s light outside. With less sunlight in the winter months, more melatonin is produced, which can cause people and pets to want more sleep.

Can Pets Get Seasonal Affective Disorder?

Although there’s no known scientific evidence that SAD affects pets, behavioral and mood changes in pets during the fall and winter months have been suggestive of SAD.

It’s believed that pets can be affected by the emotions of the people in their lives, so if you are showing signs of SAD, it’s possible your pet may show similar signs.

SAD is suspected to affect pets much like it affects humans, although assessing a dog or cat's feelings is difficult.

According to reports from pet parents in the United States, about one-third—approximately 30 million—pets show signs of changes in their mental state and energy levels during the winter months.

Symptoms of Seasonal Affective Disorder in Pets

You may notice the following behavioral changes in your pet during the fall and winter that suggest SAD:

  • Sleeping more

  • Low energy

  • Mood changes

  • Change in appetite

  • More frequent barking in dogs

  • Increase in aggression or destructive behavior, potentially due to boredom because the pet is spending more time indoors

  • Excessive shedding

  • Decreased interest in toys and exercise

  • Hiding or being withdrawn from family

  • Clinginess or seeking to always be around the family

Winter Toys and Activities for Pets

During the cold winter months, finding new and creative ways to interact and play with your pets can help change their—and your—mood.

Help to mitigate the effects of SAD by providing physical and mental stimulation, keeping to a daily routine, spending plenty of time bonding with your pet, and letting as much sunlight enter your home as possible.

Here are a few species-specific ways to keep pets “smiling” all year round:



  • Window perch

  • Short leash walks during daylight hours

  • Patio (or “catio”) time

  • Interactive toys, like laser pointers, treat dispensers, and puzzle toys

  • Cat wheel

  • Hide and seek with toys and treats

  • Catnip toys

  • Cardboard box maze or hideout

When To Call Your Vet

While SAD may affect your pet, pain or illness can also cause mood or behavior shifts.

Any time your pet’s behavior changes, the first thing to do is ensure they are healthy. Give your veterinarian a call and schedule an exam to rule out any medical issues as the cause before considering it a behavioral issue related to the seasons.

While humans with SAD can be treated with remedies such as vitamin D and omega-3 fatty acid supplements, vitamin D should never be given to pets unless it has been prescribed by a veterinarian for a specific medical condition.

The margin of safety for vitamin D supplements in pets is narrow, and serious, potentially fatal consequences can occur if vitamin D is not properly administered to pets. Omega-3 fatty acids can help with cognitive support but should always be given to pets under the guidance of their veterinarian to ensure its safety.

Does Seasonal Affective Disorder Affect Pets FAQs

Do SAD lamps work on dogs?

SAD light boxes are used to provide people with relief from symptoms of this seasonal disorder by mimicking outdoor light. They provide high light intensity with minimal UV exposure. While this therapy might not harm your pet, there is no evidence that it will help them.

Is my dog depressed or sick?

Depression in dogs is usually triggered by an event such as the loss of a loved one (pet or person) or a major life change. It’s always best to rule out any potential health issues before assuming your pet’s behavior change is caused by depression. Most behavior changes in pets are in response to illness.

Featured Image: Chalabala/iStock / Getty Images Plus via Getty Images

Barri J. Morrison, DVM


Barri J. Morrison, DVM


Barri Morrison was born and raised and currently resides in Ft. Lauderdale, Florida. She went to University of Florida for her...

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