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25 Warning Signs for your Dog's Health


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Updated: 9/21/2021

We all want our furry friends to remain in good health for as long as possible, but with the commonplace nature of diseases and the large potential for a dog to become injured in the course of daily life, it is inevitable that they will sooner or later run into a problem. Fortunately, most of the signs that something is wrong are fairly easy to spot, making it simple for dog owners like you to know when your pet is falling ill and act accordingly. Thus, we have composed a list of some of the most common signs that your dog is starting to feel unwell and what the most common root causes are.

1.Vomiting – One of the most obvious and alarming signs that something is wrong with our pet is when they start to throw up. This can be caused by many things, but it is usually due to food poisoning or the accidental swallowing of a foreign object. In extreme cases, vomiting can be caused by liver failure, as the dog tries to protect itself from any toxins that may remain in its stomach.

2. Diarrhea – Diarrhea can be a symptom of some fairly nasty health issues, including parasites, poisoning and even direct damage to the digestive tract caused by infections or foreign objects. However, while it can be caused by just a simple stomach bug, diarrhea can itself be very dangerous as it causes the dog to lose a large amount of fluid in a very short space of time, possibly leading to dehydration.

3. Lethargy – Although all dogs can act lazy from time to time, if your dog wants to lie around sleeping all day and do nothing more, then there may be a problem. Loss of energy can be caused by many conditions affecting many different parts of the body, but amongst the more serious problems are heart disease, diabetes and cancer. If lethargy persists for any great length of time, then a veterinary examination is probably needed.

4. Labored Breathing – A fairly distressing sign that a dog is in trouble is when it starts to have difficulty drawing breath. A fair number of causes can be listed, but most of them are problems that directly impact on the animal’s lungs like a chest infection or the aspiration of objects or food.

5. Persistent Coughing – If your dog starts coughing for a period of a day or two, it is most likely just due to a common cold irritating its airway. However, longer lasting coughs can be a sign of serious health problems relating to the accumulation of fluid within the lungs such as pneumonia or cardiac issues.

6. A Dull Coat – One of the easiest ways to tell if a dog is in good health or not is to take a look at their fur. The more glossy and smooth it is, the better. If however, they are suffering from fleas, malnutrition, skin diseases or a host of other conditions, it can be expected for the coat to deteriorate in quality and become coarse and matted.

7. Exhaustion – All of our pets will get tired after a long day out or after a session of good quality exercise, with muscular soreness slowing them down to boot. But, if they appear slow and unable to keep up on normal walks, it could be a sign of heart problems or some kind of digestive issue preventing them from getting the energy they need.

8. Excessive Scratching – The presence of mites and other such parasites will almost always result in the dog starting to scratch at its skin incessantly. This behavior is not just futile when it comes to stopping the itching these creatures cause, but can also cause serious damage to the skin, putting the dog’s wider health at risk from infections of the resultant wounds. Also, scratching can be caused by the dog coming into contact with irritants that can potentially have much worse consequences.

9. Excessive Licking – Although you may be accustomed to your dog licking itself as a form of normal grooming, there is a point where this behavior can be deemed unusual. If the animal is constantly focused on licking and grooming it could be a sign of illness, especially if they are concentrating on just one body part. Infections can commonly cause this but allergies and reactions to medication can also be to blame.

10. Jaundice – A yellowing of the dog’s skin should be treated as extremely serious, as this is often one of the first signs of liver or kidney failure. As the organs become unable to filter toxins out of the dog’s blood, a chemical known as ‘bilirubin’ builds up, lending the skin its yellow hue.

11. Corophagia – Eating feces is an odd behavior that everybody has at some point or another witnessed an animal indulging in. The underlying reason for this is usually malnutrition, as the dog will be trying to get nutrients directly from what was formerly another animal’s food.

12. Bloody Stool – Although concerning, you should not be immediately worried by small amounts of blood in your dog’s feces, as this can often be down to simple irritation of the digestive tract by something the dog ate. Although, if the problem persists, it can be a sign of a chronic ulcer in the intestine or even cancer, meaning the dog should be examined by a vet.

13. Dry Nose – The classic sign of ill health that all dog owners know to look out for is the dry nose. But some of the reasons behind this may surprise you. Aside from the obvious dehydration, a dry nose can also be caused by allergies (contrary to the common perception of a runny nose and sneezing) and sunburn. Note that this type of allergic reaction can often be triggered by food.

14. Bloodshot Eyes – Along with allergies, bloodshot eyes are often due to the presence of an infection. You should bear in mind that eye infections can often be very uncomfortable for the dog and if not promptly treated can spread to other parts of the body, namely the tissues of the face.

15. Persistent Sneezing – Dogs spend their lives much closer to ground level than humans, and as such are exposed to much more dust and irritants, meaning that the occasional sneeze is to be expected. Constant sneezing however, can be an indication of an allergic reaction or infection of the sinuses.

16. Whining – A dog that is experiencing significant discomfort will often vocalize to tell its owner that there is something wrong. This can mean anything from them having an upset stomach to a broken leg, so further investigation is usually warranted.

17. Muscle Spasms – Although we’ve all seen our dogs twitch in their sleep or move their legs when getting a belly rub, involuntary movements during waking hours can be a cause for concern, as they can be indicative of problems with the nervous system due to poisoning or organ failure.

18. Aggression – Although sudden temper outbursts in dogs are often depicted in popular culture as the first signs of rabies, there are in fact much more minor causes that can play a role. Hormonal problems are the main reason, with growths within the endocrine system usually triggering them. Pain from an injury can also provoke the behavior or infections causing the dog to become delirious.

19. Seclusion – Dogs are social animals who love to be showered with attention and affection, so if you notice that your dog is becoming withdrawn and avoiding contact, it can be a sure sign that something is wrong. Usually, pain and discomfort will provoke this behavior, so digestive problems should be checked for. Similarly, poisoning can provoke symptoms such as photosensitivity and abdominal pain that will cause the dog to want to isolate itself.

20. Refusal To Eat – When you become ill, you will rarely want to eat a large meal. But if your dog starts to refuse food for any significant length of time, it can mean that they are suffering from a significant problem. Liver disease often results in a loss of appetite, as can some parasitic and bacterial infections.

21. Shivering – As distinct from muscle spasms, shivering is usually a reaction by the dog to a change (or perceived change) in temperature. This usually takes the form of a fever, where the dog’s body temperature increases dramatically. Viral infections are most often to blame, but heatstroke and poisoning can also produce this reaction.  

22. Loss Of Coordination – Most poisonous plants will result in damage to the nervous system if ingested, and are some of the most common causes of an inability of the dog to manage its own movements properly. It can also result from conditions such as liver failure and breathing/heart trouble, so close attention should be paid in order to make sure the dog’s condition doesn’t worsen.

23. Limping – Animals that are suffering from injuries to their joints or muscles will usually develop a limp. You will usually notice this immediately after the injury has occurred, which provides a good opportunity to get the dog medical help. Limps can also be caused by slower-developing problems such as hip dysplasia.

24. Hair Loss – As mentioned earlier, the condition of a dog’s coat is a good indicator of its health and whilst some hair loss can be expected with age, it can sometimes be an indicator of illness. This is especially the case if it is localized to one area of the dog’s body, where any one of a number of causes (skin cancer, a bacterial or fungal infection, parasites etc) could be responsible.

25. Abdominal Pain – One of the first symptoms of a massive range of issues is abdominal discomfort. This is because a large number of important organs are located within the dog’s belly and inflammation and damage will make itself apparent within the first stages of a problem. As such, it is always a good idea to keep an eye on a dog with a sore belly, lest they should develop more serious symptoms.



There are a large number of health problems that dogs can encounter in their lifetimes, with the vast majority being relatively minor, but a minority being extremely dangerous. By having a good understanding of the warning signs that your dog may be falling ill, you can know what to expect and how to deal with it. Furthermore, having the ability to observe and understand a dog’s symptoms in the early stages of an illness can help immensely when a vet has to diagnose the problem later on, speeding up the process of your dog getting the treatment they need.

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