The Side Effects of Heartgard Heart Worm Medicine

Both dogs and cats can experience side effects due to Heartgard Plus.
Both dogs and cats can experience side effects due to Heartgard Plus. (Image: Puppies of the spitz-dog and cat in studio image by Ulf from

Heartgard Plus is a medication given once-a-month to dogs and cats to prevent heartworms and other parasites, including roundworms. While generally safe, Heartgard Plus still carries the potential for side effects. The main ingredient of Heartgard Plus is Ivermectin, which is effective in killing and preventing parasites. While many pets take Heartgard Plus without any issues, pet owners should still be aware of the possible reactions associated with the use of Heartgard Plus.

Behavioral Changes

According to, a pets information website, side effects from Heartgard Plus are most commonly seen in cases of overdose. Overdose occurs when the animal is given more than the recommended dose, which is stated on the product's label. If a dog is suffering from an overdose, it may lose its balance and coordination. In addition, dogs that generally experience Heartgard Plus side effects tend to be canines with sensitivities to Ivermectin. Cats that experience Heartgard Plus overdose may demonstrate irritation, disorientation and lack of coordination.

Gastrointestinal Problems

Cats and dogs that suffer from Heartgard Plus-related side effects can experience gastrointestinal issues as a result. Affected dogs may exhibit flu-like symptoms including vomiting and diarrhea. Cats may also lose their appetites and experience diarrhea as well.

Physical Abnormalities, another pet information website, states that dogs with Heartgard Plus side effects may exhibit tremors and shaking. In addition, dogs can become blind or weak. Cats may develop dilated pupils, and can possibly lose their eyesight. Side effects of this nature typically present themselves approximately 12 hours after Heartgard Plus administration. Collies and dogs mixed with this breed seem to be sensitive to this type of medication and should only use it under a veterinarian’s care. Dogs that already have heartworms and are given the preventatives may go into shock. Symptoms of shock can include pale mucous membranes, a faint pulse, shivering and weakness. If your dog or cat experiences any side effects from Heartgard Plus, contact your veterinarian immediately.

Related Searches


Promoted By Zergnet


You May Also Like

Related Searches

Check It Out

How to Make an Elevated Dog Feeder

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!