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Deworming your Cat

Although some deworming medications are effective against more than one species of worms, there is no medication that is effective against them all. Accordingly, for a medication to be safe and effective, a precise diagnosis is required. It is also important that the medication be given precisely as directed. Natural side effects, such as diarrhea and vomiting, must be distinguished from toxic reactions. All dewormers are poisons-ideally, they are more poisonous to the parasites than they are to the hosts. For these reasons, it is advisable to deworm your cat only under veterinary supervision.

Deworming Kittens

A very large proportion of kittens are infested with ascarids. Other worms may be present, too. It is advisable to have your veterinarian check your kitten’s stool before treating her for ascarids. Otherwise, other worms and internal parasites, such as coccidia, may go undetected.

Worm infestations are particularly harmful in kittens who are subjected to overfeeding, chilling, close confinement, or a sudden change in diet. Stressful conditions such as these should be corrected before administering a deworming agent. Do not deworm a kitten with diarrhea or other signs of illness, unless your veterinarian has determined that the illness is caused by an intestinal parasite.

Kittens with ascarids should be dewormed at 2 to 3 weeks of age and again at 5 to 6 weeks. If eggs or worms are still found in the stool, subsequent treatment should be given. Due to public health considerations, many veterinarians recommend deworming kittens with a safe dewormer every month until 6 months of age.

Deworming Adult Cats

Most veterinarians recommend that adult cats be dewormed only when there is specific evidence of an infestation. A microscopic stool examination is the most effective way of making an exact diagnosis and choosing the best deworming agent.

It is not advisable to deworm a cat who is suffering from some unexplained illness that is assumed to be caused by worms. All dewormers are poison-meant to poison the worm, but not the cat. Cats who are debilitated by another disease may be too weak to resist the toxic effects of the deworming agent.

Cats of all ages, particularly those who hunt and roam freely, can be subject to periodic heavy worm infestations. These cats should be checked once or twice a year. If parasites are identified, they should be treated. It is reasonable to deworm outdoor cats routinely for ascarids and tapeworms, even without a positive stool sample. Many anthelmintics are safe for repeated use. Tapeworms segments may be seen frequently, and when discovered, they should be treated. Cats with tapeworms may need to be treated as often as four or five times a year.

A queen should have her stool checked before breeding. If parasites are found, she should receive a thorough deworming. This will not protect her kittens from all worm infestations, but it will decrease the frequency and severity of any parasite infestation. It will also help to put her in the best condition for a healthy pregnancy.

WebMD Veterinary Reference from "Cat Owner's Home Veterinary Handbook"

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