What are the Side Effects of Revolution Heart Worm Medicine for Dogs?

Revolution is a monthly topical heartworm preventative medication that also protects dogs and cats against fleas, ticks and ear mites. Revolution contains selamectin, an antiparasitic agent that also works against feline hookworms, feline roundworms and sarcoptic mange, according to veterinarian Dawn Ruben. Revolution is only available with a prescription from a veterinarian and is relatively safe, but it does have some side effects, especially for debilitated or underweight dogs.

  1. Loss of Appetite

    • While obvious side effects are rare with Revolution, they can include loss of appetite, excess salivation, diarrhea, vomiting, muscle tremors, fever and rapid breathing, according to Doctors Foster and Smith Pharmacy. These symptoms can be mild or severe, and a dog experiencing the side effects should see a veterinarian for a checkup.

    Hair Problems

    • Revolution is a liquid medication applied to a spot on the dog's neck. At the application site, you might see stiff hair, clumping of hair, hair discoloration, hair loss, skin irritation or a powdery residue. These side effects are not serious, but if the skin irritation or hair loss persists for more than 24 hours it is advisable to see a veterinarian.

    Allergic Reaction

    • It is possible for a dog to be allergic to Revolution. Symptoms of Revolution allergy include facial swelling, hives, scratching, sudden onset of diarrhea, vomiting, shock, seizures, pale gums, cold limbs or coma. A dog showing any signs of an allergic reaction to Revolution should see a veterinarian immediately for treatment.