ProHeart 6, a heartworm “preventative” shot providing 6 months of protection against canine heartworms, is back on the market after having been pulled from shelves in 2004 by manufacturer Fort Dodge. More than 5,000 adverse “events,” including hundreds of canine deaths, prompted the FDA to request the drug’s withdrawal. It is being brought back under a “risk minimization action plan” and restricted use program (including vet training and informed consent notification) — an uncommon plan to try to limit damage from the drug.
I wonder, why is ProHeart 6 so indispensable that it must be brought back? There are safer once-a-month heartworm “preventatives.” More importantly, there are countless natural, non-toxic alternatives. (By the way, heartworm drugs do not “prevent” heartworms. They kill them.)
Does a risky six-month remedy have any real value? Not to me as loving guardian to two dogs, and certainly not to the dogs themselves who may suffer potentially lethal adverse reactions. The main value will be to Fort Dodge stockholders and to the vets who benefit from the sale of the product plus the office visit to give the shot.
Before writing about heartworms and other parasites for my book, Scared Poopless: The Straight Scoop on Dog Care, I interviewed three veterinarian-authors and two other holistic vets, and also spent months reading and doing on-line research. Every vet I consulted thought heartworm medications were toxic. Dr. Martin Goldstein, renowned veterinary and author, has written that he sees heartworms as less of an epidemic than the “disease-causing toxicity” of heartworm medicine.
No discussion of this medicine would be complete without a study of the heartworm life cycle. Microfilariae, which grow into heartworms, must be injected into dogs by female mosquitoes. No mosquitoes, no heartworm infestation. Dogs with poor diets, and those suffering from immune system dysfunction, are particularly susceptible.
Most U.S. locales don’t have mosquitoes in cold weather. But even if mosquitoes are present, according to the University of Pennsylvania vet school, microfilariae require sustained periods of weather above 80 degrees and not below 57 degrees (Fahrenheit) to develop to the proper stage to be delivered.
Thus, protection against heartworms is unnecessary year round in many locations. Read more about the mosquito’s life cycle at a website owned by ProHeart manufacturer Fort Dodge, click here. For an unbiased look at nationwide incidences of heartworm and drug adverse reactions, click www.dogsadversereactions.com/moxidectin/heartwormmaps.html
I live in Southern California, an arid area with few heartworm cases. For my own dogs, I use non-toxic alternatives: natural non-toxic bug repellent and keeping the dogs indoors when mosquitoes are buzzing. I also make sure there is no standing water in my yard.
I increase safety by testing my dog’s blood once yearly for heartworm antigens, something also required if they were to take heartworm “preventatives.” If I lived in an area with sustained hot weather and lots of mosquitoes, I’d test twice yearly. Heartworm infestation is generally curable when caught early. The current canine movie star “Benji” is a heartworm survivor.
A follow-up: Still considering giving your dog ProHeart 6 for heartworm protection? ProHearts’ own Client Information Form lists adverse reactions: “These can include (but are not limited to) allergic responses, lethargy (sluggishness), seizures, vomiting and diarrhea, itching at the injection site, fever and, in rare instances, death.” Read the entire Proheart form at (Note: To enlarge the print size, change it to “100%” on the toolbar underneath the word “Help.”)
An article from the FDA worth reading reports “the side effects…anorexia (loss of appetite); lethargy; vomiting; neurologic signs, such as seizures, difficulty walking and reports of blindness; jaundice (a yellowish appearance); and bleeding disorders. Most of these observable clinical signs have occurred within one month of receiving the drug.” www.fda.gov/cvm/PH6QA.htm
To comply with the FDA’s “risk minimization” plan, Fort Dodge is implementing an educational and communication program that will require veterinarians to register with Fort Dodge and complete “in-depth” training as a condition of purchasing ProHeart 6. A letter from the FDA explains vets will also have to “confirm they have completed the in-depth training, read the new label, the conditions of use, the requirements to provide the dog owner with the Client Information Sheet and obtain signed informed consent, record the product lot number in the medical record, and report adverse events. Veterinarians are also advised to obtain baseline history, physical exam, and blood-work parameters prior to administration of the drug to confirm the patient is an appropriate candidate for ProHeart 6.” Read the entire letter at http://www.fda.gov/cvm/ProHeart6AVMA.htm
In-depth heartworm articles:
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