Over-the-Counter Heartworm Medicine for Cats

Heartworm medicine for cats comes in the form of chewable tablets or as a topical solution to be applied on the skin. It is better and cheaper to prevent heartworm than to cure it. Heartworm in cats can cause sudden death with no previous symptoms. If you live in a mosquito-infested area, you should consider preventing heartworm in your cat. Never use canine heartworm medicine on your cat.

Symptoms of Heartworm in Cats

Some cats live with heartworm and show no symptoms, and then die suddenly. Most commonly the symptoms of heartworm in cats are those of feline asthma (coughing, difficulty when breathing) or vomiting (which, in cats, can be a symptom of various diseases). Therefore, rather than being able to cure heartworm in time, it's best to talk with your veterinarian and take preventative measures, especially if you live in an area with mosquitoes, which spread the heartworm larvae.

Preventative Measures for Heartworm in Cats

The most common form of feline heartworm medicine the chewable tablets. They can be administered daily or monthly. If you cannot afford giving the treatment throughout the year, you can skip the cold months when mosquito bites are not as common. However, if the cat has missed more than a few months' treatment, it is recommended that you have your veterinarian test him for heartworm.

The most common oral preventatives for heartworm include:

  • Heartgard, is a preventative of heartworm disease in cats and dogs. It's also used to protect cats against hookworm. It comes as tablets that are chewable. Heartgard can be given all year round or only during mosquito months. The active ingredient is in Heartgard is Ivermectin.
  • Nuheart, which contains Ivermectin and should be given monthly to the cat.
  • Interceptor, which contains Milbemycin oxime. It's effective in the prevention of heartworm disease as well as hookworm, whipworm and roundworm.

Topical heartworm medicine is applied and absorbed through the skin. Common forms include:

  • Revolution, which has Selamectin as an active ingredient and is effective against heartworms as well as fleas, ear mites, hookworms and roundworms. The ointment is to be applied directly on skin, not on the coat, but somewhere where the cat cannot lick it (such as the base of the skull). One tube of Revolution should last for about one month. The product should not come in contact with the cat's eyes or mouth, and you should avoid getting it on your skin. The product can be used in kittens over 8 weeks of age.
  • Advantage Multi for Cats (Advocate), which contains Imidacloprid and Moxidectin. Advocate can be applied monthly and in addition to preventing heartworm, it also prevents fleas and other gastrointestinal worms and mites. The product can be used in kittens over 9 weeks of age.

Some gastrointestinal worms in cats can also be transmitted to humans, so you should be very careful when you clean up the cat's stools.