Does my cat really need this medication?

Does my cat really need this medication?


Dear Dr. Evans,

My vet suggests I put my indoor cat on heartworm preventative year-round. Seriously? I mean, she’s not a dog and she never goes outside. Is this for real? I didn’t even know cats could get heartworm.
—Joe Skeptic

Dear Joe,

Well, they can and they do. Heartworm, as most dog owners know, is spread by the bite of an infected mosquito, and what home is mosquito-proof? In dogs, the parasite develops through several larval stages before setting up shop in the heart as adult worm. While cats are not the natural host for heartworms, they can also become infected, and the disease is serious. It can cause a respiratory problems like coughing and difficulty breathing; sudden unexplained death has been known to happen. The disease can be very tough to diagnose (there are a lot of false negatives associated with the tests) and there is no cure — only supportive treatment.

Being an indoor cat in the Northeast isn’t as much help as you might think. Of all cats confirmed positive for heartworm, twenty-five to thirty percent of them are strictly indoors. Years ago, heartworm was considered to be largely a disease of subtropical areas and, in the U.S., the south. But these days, heartworm disease is present in all fifty states. Dog owners used to be told to give preventative medication from spring to fall, but we now recognize that the disease can be transmitted to cats or dogs in any month of the year. Winter weather has been unpredictable in recent years — I’ve killed a mosquito or two in January.

Prevention is easy. Most preventative medicines are in the form of a very palatable treat or are applied to the skin of the back of the neck, much like the most popular flea and tick preventatives. And as a bonus, there are several products on the market that treat a broad range of parasites, such as ear mites, roundworms, hookworms, and fleas — a lot of bang for the buck. Meticulous parasite prevention carries a big payoff, because in addition to whatever problems any given parasites can cause, many of them also spread disease (ticks spread Lyme disease, and not just to dogs) and even other parasites (fleas spread tapeworms).

When I first started practicing, I always felt a little guilty telling clients that parasite control was possible. It was, technically, but at the cost of a massive effort and risk of side effects. But for the past twenty years, parasite control has been so safe, effective, and easy that there’s no excuse not to protect even your indoor kitty from parasites.

Dr. Lynn Anne Evans of the Barrington Veterinary Clinic has been practicing veterinary medicine for 26 years. Do you have a pet question for Dr. Evans? Please email [email protected], with “Dr. Evans” in the subject line.