Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Do Dogs Know When You’re Sick? The Interesting Answer!

sick man lying in bed with his dog

Dogs are considered man’s best friend for various reasons. They are incredibly loyal and entertaining, and they’re good at keeping their human companions company when nobody else is around. Dogs also happen to be highly observant. So, does your dog know when you are sick? It turns out that they might be able to tell when you’re sick! Here’s how.

divider dog paws 3 oct 2024

A Dog’s Nose Can Tell Them About Your Health

A dog’s nose has about 300 million olfactory receptors1, which is over 6 million more than humans have. Dogs can also process smells better than we can. So, while we can’t smell someone’s odor changes due to a change in volatile organic compounds within the body, a dog likely can.

For instance, a diabetic human’s bodily compounds change when their blood sugar levels rise or fall. A dog trained to do so can smell the change in compounds and alert their companion to the blood sugar irregularities2. Some dogs also seem to be able to detect cancer by smelling a human’s breath, skin tissue, or urine3.

dog nose close up shot
Image Credit: Miranda, Pixabay

So, it makes sense that a dog can detect when you are sick, even with a cold, as your organic compounds will change and produce a different smell than would be produced when you are in good health. However, a dog must know how a person normally smells to detect a change in their body chemistry.

Therefore, your dog might be able to detect when you are sick, but chances are that they would not be able to detect an illness in someone they have never met or don’t know well. The exception is the dogs trained to detect the specific scents of cancer or other illnesses. In that case, they should be able to detect cancer or illness in anyone’s saliva or urine sample that they sniff.

It’s Not Just About a Dog’s Nose

Most dogs are good at understanding their companion’s body language and changes in behavior. They also know every aspect of their owner’s daily routine and use that routine to give themselves confidence that everything is going smoothly.

If you are not feeling well, you might rest or blow your nose more than usual. You may groan when getting up to make food or complete other tasks. You might even be a bit grumpy with everyone around you. You might drink more liquids to stay hydrated. Whatever the changes in your behavior, your dog will notice and understand that something is wrong.

How Dogs Might Respond If They Realize That Their Companion Is Sick

All dogs are different, so their response to detecting illness in their pet parents can vary. Most dogs will stick closer to their companion’s side throughout the day as if watching over them. They might pace back and forth nearby during a nap or movie-watching session. Your dog’s reaction might be subtle and hard to identify if they are already naturally cuddly and interactive with you.

girl hugging her pyschiatric service dog
Image Credit: Africa Studio, Shutterstock

divider dog paws 3 oct 2024

A Quick Recap

Research shows that dogs can detect when their human companions are sick. Trained dogs do a better job of doing so; however, untrained dogs may not react to their detection of an illness. It depends on the dog, their instincts, and their ability to communicate their concerns with those around them. It’s not a good idea to rely on a dog to detect when you are ill, as they may not alert you. Whenever you feel sick, you should schedule an appointment with your doctor.


Featured Image Credit: Aleksey Boyko, Shutterstock

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

Ask Dr. Paola- Sores, Hearts & HIV (April 14, 2025)

Welcome to our “Ask Dr. Paola” series, where every Monday we bring expert advice straight from Dr. Paola Cuevas (MVZ) to help our...

Adequan for Dogs: Uses, Side Effects & History (Vet Answer)

If your dog has osteoarthritis, your veterinarian may have prescribed a drug called Adequan. Adequan improves the quality of joints, which can increase...

Alabama Rot in Dogs: Causes, Signs & Treatments (Vet Answer)

Two words that have been the source of great stress and anxiety amongst vets and dog owners: Alabama rot. More correctly known as...

Ear Dermatitis In Dogs: Our Vet Explains the Signs, Risks & Treatment 

Ask any general practice veterinarian what type of ailments they see most often in dogs and I will guarantee you that skin and...

More related

Top Dog Academy Review 2025: Our Expert’s Opinion

Review Summary What Is Top Dog Academy? How Does It Work? Whether you’re a first-time dog owner or are simply dealing with a...

12 Essential Shih Tzu Supplies To Get You Started: 2025 Vet-Reviewed Guide

The Shih Tzu is a beautiful small dog breed that is quite popular for its appearance and adorable personality. It’s exciting to bring...

What Is the Best Crate Size for a Beagle? Tips & Recommendations

A dog crate plays an important role in training your pup. It provides a den-like space that feels safe and secure, it keeps...

Belgian Tervuren vs Malinois: Differences Explained (With Pictures)

Belgian Tervuren and Malinois are two wonderful dog breeds that have a shared heritage but distinct personalities and characteristics. Hailing from Belgium, they...

Keep reading

7 Best Budget-Friendly Dog Foods in 2025 – Reviews & Top Picks

Feeding our dogs can be a monumental task. Sometimes it does seem like they never stop eating! The cost of food and treats can add up quickly and leave pet parents scouring the recesses of the internet and ad booklets...

labrador with its food close up

7 Best Nom Nom Dog Food Alternatives in 2025: Reviews & Top Picks

Nom Nom is a dog food subscription service. You sign up, choose your dog food and delivery rate, and you can have dog food delivered to your door. It provides the benefits of feeding a freshly made diet, combined with...

dog eating wet food

5 Benefits of Sweet Potatoes for Dogs: Vet-Reviewed Facts & Considerations

Sweet potatoes are superfoods chock full of many health benefits for humans. They’re loaded with vitamins and minerals and are generally considered a healthier choice than regular potatoes. Since they’re so beneficial for humans, you might wonder if sweet potatoes...

dog smelling the homemade cooked sweet potato on plate

Can Dogs Eat Falafel? Vet Reviewed Facts & FAQ

Falafel is a typically vegan-friendly Middle Eastern dish made of chickpeas or fava beans, spices, herbs, garlic, and onions and that is often served up with pita bread, tahini sauce, and with a side of salad. Now, falafel is an...

Can Dogs Eat_falafel

Why Does My Dog Eat My Hair? 10 Possible Reasons (Vet-Reviewed)

Ever caught your canine companion munching on your hair and wondered why? It’s not a gourmet meal, after all. This behavior, while strange to us, is anecdotally quite common and can be attributed to various causes. From their inherent grooming...

woman carrying smiling dog

9 Best Dog Foods for Seizures in 2025: Reviews & Top Picks

Seizures are a growing concern amongst dog parents and one that is understood as little by veterinarians as it is by dog owners. While there is debate on the cause and necessary treatment for seizures in dogs, there’s no doubt...

Dog beagle eating canned food from bowl in bright interior

15 Foods With Vitamin E for Dogs: Vet-Approved Options

Vitamin E is an essential vitamin for canines. It is an antioxidant that helps clear free radicals from your dog’s body, supports vision, promotes healthy bone growth, helps the reproductive system function, and supports the immune system. Their food should...

english bulldog eating pumpkin

American Journey Dog Food Review 2025: Pros, Cons & Recalls

Review Summary Introduction American Journey dog food has quickly become a favorite of dog parents everywhere. However, if you’re searching for it in your local pet store or even online, you are not likely to find it. This brand of...

Dogster_American Journey Dog Food Review