4 min read


Can Dogs Sense if You're Sick?



4 min read


Can Dogs Sense if You're Sick?


Have you ever had a cold or the flu and your dog seems extra affectionate? Maybe they cuddle with you more, lay in bed with you, or hang out by your side while you lie on the couch. If you notice this behavior, it is for a reason and it is not just a coincidence. This may have prompted the idea that your dog may know when you are feeling under the weather, and the cool thing is your dog most certainly can tell when you are sick! 

Not surprisingly, your dog knows when you are sick due to their amazing sense of smell - and a few other factors we will explore below. 


Signs of a Dog Knowing You are Sick

Your dog can tell you are sick for a variety of reasons and they will make this fact known by showing certain signs in your presence. Firstly, your dog is going to seem extra cuddly and like they love you just a little bit more than they usually do. If you are sick and you find your dog is constantly trying to lay on the bed or couch with you, if they always want to place their head in your lap, or just be somewhere close to you, they are trying to comfort you more and let you know they are there for you. 

Your dog may also be a little calmer in your presence, be less demanding of walks and playtime, and they may even pull less or be less excited on their walk if they know you are not feeling your best. This is because they know you are tired and your energy is much lower than it normally is. 

They pick up on your cues and adjust their behavior accordingly. Your dog wants to make you feel better, comfort you, and lower your stress levels when you're sick and this is how they attempt to do just that. 

Body Language

These are some signs you may notice if your dog senses you are sick:

  • Wag Tail
  • Hugging
  • Whale Eye
  • Sleepiness

Other Signs

Here are some other signs you may notice if your dog senses you are sick:

  • Are Less Energetic And Demanding
  • Staying Close To Your Side
  • Laying And Cuddling With You A Lot

History of Dogs Sensing People are Sick


A dog's sense of smell has always been a powerful and amazing trait, even when dogs were undomesticated and wild. Dogs rely on their sense of smell for many different things, from hunting for food to sniffing out their favorite stuffed animal toy! Dogs sense illness through the chemical changes in our bodies, so it is likely dogs were able to detect illness in their humans for thousands of years. 

Dogs are also able to detect sickness in fellow dog companions, as well. If you have ever seen a dog intently licking a spot on another dog and then find there is a sore or scrape there, this is because the dog can sense it and they are trying to help the affected dog. 

However, it was not until relatively recently that science has been able to confirm how dogs are able to sense illness and that they can indeed sense illness in humans and other animals. Dogs are now specifically trained to detect illnesses in humans. Some dogs are trained to actually detect the early stages of cancer in humans and not just minor illnesses like a cold or the flu. 

Science Behind Dogs Sensing When You're Sick


When a person is sick, there are certain chemical changes in their body that can be detected by a dog's keen sense of smell. In particular, they are able to detect VOCs (volatile organic compounds) that aid in the early detection of illness and that includes cancer as well. 

When we are sick, our happiness receptors and hormones like serotonin, dopamine, and oxytocin reduce. Dogs can pick up on these small changes as well and they may even know you are getting sick before you become aware! Your lack of energy will also be picked up by your dog as well. They are able to sense your emotions and pick up on facial cues that let them know you are not yourself.

Training Dogs to Sense Sickness


You will not need to train your family dog to sense and detect when you are sick as your dog is able to pick up on these subtle changes all on their own. Your dog will just know and there is nothing you need to teach them to help them detect such changes. 

However, special dogs are trained to sense and detect more serious illnesses, diseases, and cancers. These kinds of dogs are known as medical detection dogs and they go through similar training as a bomb or drug-sniffing dog would. 

Take diabetes for instance. Dogs are trained to sniff out diabetes patients in a very special way. These dogs are rewarded when they are able to detect a low blood sugar level in specific samples. This teaches them to just pick up on that specific scent and none of the other scents they come in contact with during certain situations. 

For illnesses like cancers, dogs will work in a laboratory-based environment and work with blood samples to detect whether or not a blood sample is likely to test positive for a certain type of cancer. Again, these dogs are rewarded when they correctly identify a sample as having the scent marker for that sickness, disease, or cancer. 

Dogs also have the ability to train to detect a heart attack before it happens, seizures, behavioral changes, and more. 

Have questions or concerns about your pet?

Chat with a veterinary professional in the Wag! app 24/7.

Get Vet Chat

By a Samoyed lover Kayla Costanzo

Published: 04/16/2018, edited: 04/06/2020

Wag! Specialist
Need to upgrade your pet's leash?

Learn more in the Wag! app

Five starsFive starsFive starsFive starsFive stars

43k+ reviews


© 2023 Wag Labs, Inc. All rights reserved.