Pet Lethargy: An Emergency, Or Not?

Have you ever noticed your pet sleeping more than usual, appearing uninterested in their typical playtime or walk, or even not wanting to get up from their bed or resting spot? When your pet is lethargic, it can indicate that they may be seriously ill, but pets can also have an “off day” and be completely fine. With troubling symptoms such as lethargy, knowing when to “wait it out” and when to call your primary care veterinarian or The COVE for emergency care can be hard to determine. Luckily, we can shed some light on this common but often vague symptom in cats and dogs.

What is Lethargy in Pets?

Lethargy is sometimes described as extreme tiredness or weakness, but it’s more than that. Pet lethargy is a symptom of various illnesses and conditions requiring immediate action. For example, your pet may suddenly withdraw from the household or gradually become less active. Deep unresponsiveness, inactivity, or extreme tiredness characterize true pet lethargy, but even a pet that plays less than before can be suffering from a health problem.

Always keep a close eye on changes in your pet’s behavior, especially eating, drinking, grooming, and bathroom habits. Pets are masters at hiding subtle signs of illness from even their closest people, but a simple test would be to measure your pet’s interest in the goings-on around them and to offer a favorite treat to check their responsiveness.

Common Causes of Lethargy

The list of conditions that cause lethargy is vast. A lethargic pet can be affected by simple muscle soreness but can also suffer from acute or chronic illnesses.

Some common reasons your pet may be lethargic include the following:

  • Anemia
  • Arthritis or joint disease
  • Chronic diarrhea or vomiting
  • Dehydration
  • Diabetes
  • Difficulty whelping
  • Foreign body obstruction
  • Heart, kidney, or liver disease
  • Heatstroke
  • Immune system diseases
  • Infectious diseases
  • Injury or trauma
  • Obesity
  • Pain
  • Poisoning or exposure to toxins
  • Reactions to certain medications
  • Snakebite

Are They Lethargic, or Just Tired?

Sometimes, our typically energetic and otherwise healthy pets get tired from a good run or an especially rambunctious play session at the dog park. Young pets can become sluggish from mild muscle soreness and will be back to their usual selves after some extra rest. If your pet will still eat and go for a walk, giving them a little time before racing into the emergency room is reasonable. While recuperating, observe your pet closely for other signs of illness, allow them to rest quietly without being disturbed by other pets or family members, and be ready to act quickly should their condition deteriorate.

Pets (cats, especially) can also become lethargic from psychological distress, such as a change in their routine due to a new baby, the addition of a new pet to the household, or a move. This more subtle form of lethargy can sometimes be helped with time and some extra attention, but if that doesn’t solve the problem, then make an appointment to see your family veterinarian. Again, if other symptoms accompany the lethargy, call us right away.

When Lethargy is an Emergency

If your pet has been lethargic for more than 24 hours, has been increasingly lethargic, or is unresponsive, don’t wait — it’s time to have them seen immediately. In addition, anytime lethargy is accompanied by other signs of illness or if there has been recent trauma, always seek advice right away.

Signs of illness when accompanying lethargy that are particularly concerning include:

  • Avoiding contact with family/ hiding
  • Decreased appetite/ refusing food
  • Fever
  • No urination for over 24 hours
  • Pain
  • Shivering/shaking
  • Unable to stand
  • Vomiting/diarrhea
  • White or pale gums

Please don’t hesitate to come in or call us anytime at (757)935-9111; we will happily assist you. For non-urgent patients, we may recommend contacting a telemedicine service such as Vetster, which offers 24/7 on-demand consultations.

Please understand that if you visit, we may ask you to wait. Although we care about every pet, we must prioritize the most urgent pet patients, including those who arrive after you.


About Us

The COVE’s veterinarians and staff wholeheartedly embrace the core values of community, collaboration, commitment, compassion, and integrity. This focus ensures that pets, the people who love them, and their primary care veterinarians have as positive and affirming a healthcare experience as possible, regardless of the circumstances that bring us all together.