Cat Dewormer Side Effects

A cat dewormer is meant to rid a feline of harmful parasites. However, these products have side effects that cat owners should be aware of.

Parasites in Cats

A parasite is an organism that has a symbiotic relationship with its host. However, the relationship is at the host's expense, as the parasite can live within or on top of a cat. The prevalence of parasites in cats is high, up to 40% or more. A parasite may be worm-like, made of a single cell or can be an insect.

Parasites that enjoy the company of a cat include:

  • Heartworms
  • Roundworms
  • Hookworms
  • Tapeworms
  • Pinworms
  • Whipworms

Cats can acquire parasites from dirty water, fleas, mosquitoes, ticks, feces, rodents and soil. Kittens can become infected with parasites before they are born if the mother had a dormant infection. Parasites can even be passed through the queen’s milk. Symptoms of a parasitic infection include:

  • Vomiting
  • Diarrhea
  • Dehydration
  • Anemia
  • An unhealthy coat
  • A distended abdomen

Deworming a cat that doesn’t seem to have worms is common, as this is done as a precautionary measure. Many times a cat will not show symptoms of a parasitic infection until the infestation is severe.

Cat Dewormer Side Effects

Side effects in adult cats from deworming are usually seen within 24 hours of taking a deworming medicine, but they are usually rare. Cats that have more side effects are those that are young, weak or ill. Cats with kidney problems are also more prone to suffer from side effects after taking a dewormer.

The most common side effects seen in cats are:

  • Vomiting
  • Loss of appetite
  • Increased salivation
  • Diarrhea

Other side effects a cat may have after receiving a dewormer can include salivating, lethargy, and non-alertness. One may also notice worms in the cat's stool. Side effects that should receive veterinary care within a day of the cat taking the medication include non-alertness, twitching, vomiting within an hour after taking the dewormer and irritability.

A deworming product that was once popular had side effects that caused great concern in the veterinary community. They included facial swelling, rashes, difficulty breathing, autoimmune disorders and seizures.

Kittens are known to experience side effects after taking a dewormer, especially diarrhea and sleepiness. Pet owners should always make sure the small cat drinks a lot of water so he doesn't get dehydrated. Symptoms of dangerous side effects in kitten include a lack of energy, weakness, the cat feels cold or hot to the touch, muscle tremors, blood in his stool, and white gums. If a kitten displays any of these dangerous side effects, he should be taken to a veterinary clinic immediately.

The best side effect of a deworming product is that it will eliminate the parasites that want to hitch a ride in a cat.

Parasitic infections are common, but can be prevented or eliminated with the use of a dewormer. A cat owner should always consult a veterinarian before giving a cat a dewormer, so the proper medication and doses can be administered.