“Be aware.” “Death sentence.” “Killed my cat within hours.”
Not exactly what you want to see when you’re considering a flea medication for your pet. But it’s what you see on viewpoints.com under reviews for Comfortis, a brand of FDA-approved, chewable tablets designed to kill fleas in dogs and cats. In 129 reviews on Viewpoints, the medication gets 3.2 out of five stars. Some of the review headlines are also quite positive, including: “Works for me.” “Love this product.” “A wonderful product so far!”
Trifexis, a chewable tablet designed to kill fleas, prevent heartworm disease and treat adult hookworm, roundworm and whipworm infections in dogs has also come under fire. In fact, there is a Facebook community page called “Does Trifexis Kill Dogs?”
Pet owners want to keep pets healthy and parasite-free. But what are the risks of flea, tick and other parasite medications? How do those risks compare to those associated with pest infestation?
“All of these products can lead to severe adverse effects, but thankfully these are rare,” said Dr. W. Jean Dodds, a veterinary diagnostician and researcher and owner of Hemopet in Garden Grove. “Common sense dictates that the benefits and risks be considered before any of these products are used.”
Pest problems
O.C. veterinarian Dr. Amanda Aldridge said the most common parasites dogs and cats are vulnerable to via skin are fleas, mites, ticks and mosquitoes. She said that fleas not only cause itching, but many pets have flea-induced skin allergies that typically cause secondary bacterial skin infections and severe itching. Plus, pets can eat fleas that carry tapeworm, which can cause diarrhea, vomiting and weight loss.
Mosquitoes can cause itching and are carriers of heartworm. Skin mites cause hair loss, itching and skin infections, and some types are contagious to people and other pets.
Ticks attach to the skin and cause irritation and abscesses. They can also carry dangerous bacteria and microscopic parasites, including Lyme, Ehrlichia, Rocky Mountain spotted fever and Babesia.
“These infections may cause lethargy, fevers, lameness, transient skin edema, anemia and kidney disease, which can be resolved with appropriate medical care if diagnosed in a timely manner,” Aldridge said.
Risk assessment
Learning about the risk of pests is enough to make many pet owners run to the vet or pet store for a pest medication. But there are other considerations.
According to Garden Grove veterinarian Dr. Robert E. Woods, whether to use pest medications depends on the individual dog’s lifestyle, environment and other factors. For example, if your dog is out running in fields and hiking trails daily with high exposure risk, flea and tick protection may be warranted.
Then there’s the consideration of breed disposition, size of the animal and health problems. He says cats can get seizures from pyrethrin and permethrin contained in many over-the-counter products, which he doesn’t recommend. If a pet has a neurological problem such as seizures, you need to avoid Comfortis and Trifexis. If your pet has a chronic health problem like an autoimmune disease, you also want to limit exposure to pest medications. And you always want to use medications as labeled and instructed by your veterinarian – never share a medication with another pet. Also, space apart medications.
“There are definitely times when animals have died or had some serious illness but it’s pretty infrequent from what I’ve seen in practice,” he said. “All of them are medications, so they all have potential to cause problems.”
Chemical free
Some pet owners choose natural options. According to Dodds, these can include human-grade brewer’s yeast, diatomaceous earth, garlic in moderation, citronella and other herbal shampoos, essential oils, citrus juices (but not citrus oils), and commercial natural products from reliable sources.
“Even just bathing in water can help. Keep areas clean with regular vacuuming, and keep pet rugs and beds laundered. Keep back and front yards cut short,” she said. “Many are effective, when combined with grooming to remove any parasites, and bathing with safe medicated shampoos.”
