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5 Symptoms of Heartworm You Probably Didn’t Know About

Heartworm is a serious and potentially fatal condition that affects dogs and cats. While most pet owners are aware of the common symptoms of heartworm, such as coughing, fatigue, and weight loss, there are several lesser-known symptoms that can be just as important to watch out for. In this article, we'll go over five symptoms of heartworm that you probably didn't know about and why it's crucial to stay vigilant about your pet's health.


Loss of Appetite

A significant drop in appetite can be a sign of heartworm infection, especially if accompanied by other symptoms. In a study published in the Journal of Veterinary Internal Medicine, nearly 40% of dogs with heartworm showed a loss of appetite as a symptom. If your pet is suddenly eating less or losing weight, it's important to take them to the vet for a check-up.


Difficulty Breathing

Heartworms can block airways, making it difficult for your pet to breathe. This can lead to panting, wheezing, and other breathing difficulties, even when your pet is resting. In severe cases, heartworms can even cause respiratory failure. A study by the American Heartworm Society found that over 60% of dogs with heartworm showed symptoms of respiratory distress.


Swelling in the Abdomen

Heartworms can cause swelling in the abdomen, which can be noticeable as a distended belly or an increase in weight. This swelling is due to fluid build-up caused by the presence of heartworms in the bloodstream. In a study by the Journal of Veterinary Internal Medicine, almost 30% of dogs with heartworm showed symptoms of abdominal swelling.


Exercise Intolerance

A study published in the Journal of the American Animal Hospital Association found that over 50% of dogs with heartworm showed symptoms of exercise intolerance. That’s because heartworms can make it difficult for your pet to exercise and can lead to fatigue, especially after physical activity. This can be due to the heartworms affecting the heart and lungs, making it harder for your pet to get enough oxygen during exercise.



In severe cases, heartworms can cause fainting, which can be life-threatening. This can occur when the heartworms block blood flow to the heart, leading to decreased oxygen to the brain.


Heartworm is a serious condition that can have a significant impact on your pet's health. Keeping an eye out for these lesser-known symptoms, in addition to the more common ones, can help you catch heartworm early and get your pet the treatment they need. Regular visits to the vet, along with monthly preventative medication, are the best ways to protect your pet from heartworm.


When you sign up to Pet Lovers Club monthly parasite protection, you never have to worry again about protection, because it’ll be delivered monthly to your door. That’s the hard work done for you. So don't wait until it's too late, stay vigilant about your pet's health and do the right thing to keep them safe.


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