What Can I Give My Dog for Heartworms?

Consult your veterinarian before giving your dog anything for heartworms.
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A visit from a mosquito can have a devastating effect on a dog. The mosquito is a vector for heartworm, whose larvae enter the dog's body through the mosquito's bite, setting the stage for infestation that may last for years and bringing about the onset of serious complications. Preparations designed to kill heartworm are toxic to some dogs, so consult your veterinarian for her recommendations in choosing a heartworm preventive or treatment.

Staying Worm Free

A monthly heartworm regimen prevent the parasites from taking hold in your dog. While all antiparasitic medications have toxic qualities, milbmycine oxime has the lowest amount of reported side effects, followed by ivermectin. The parasiticides are also effective in killing roundworms, hookworms and whipworms. If you suspect your dog has heartworm, do not give heartworm preventives to your dog until you talk to your vet, as large amounts of the larvae dying at once in an infected dog can cause shock or death. A vet will not prescribe most heartworm preventives without doing a test to rule out the existence of heartworm in a dog.

When Worms Take Over

If your dog is diagnosed with heartworm infestation, he'll usually receive a series of injections with the anti-parasitic drug Immiticide to kill the adult worms. After three weeks, followup injections with imidacloprid and moxidectin kill the immature worms circulating in the bloodstream. The treatment costs about 15 times more than a year's worth of heartworm preventive medication, according to the American Heartworm Society, and sometimes results in serious side effects from many larvae dying off at once or even from the medication itself.

An Alternative Treatment

Treatment of heartworm with antibiotics renders the female heartworm sterile. The treatment works because the female heartworm relies on the Wolbachia pipientis organism she carries to reproduce. When combined with low doses of ivermectin on a weekly basis to kill larvae already circulating in the blood stream, the treatment is effective, less toxic and less expensive than traditional treatment but takes 33 weeks to complete. Doxycycline has proven to significantly reduce side effects and inflammation during the course of traditional treatment, as well.

Natural Alternatives

While no research has proven natural alternatives to be reliably effective in the treatment of heartworm, consult your holistic veterinarian for a regimen that may be right for your dog. Natural remedies for intestinal parasites do not work for heartworm, as the parasite resides in the bloodstream. Natural substances that cross into the blood stream -- such as active ingredients in black walnut powder and garlic -- are toxic if given in the wrong dosage, so veterinary assistance is crucial to their success.