Oral dewormers are positioned for intestinal parasites. Dosing is by body weight and the route is direct, but success depends on how well the cat accepts a pill.

Broad-spectrum spot-ons combine some internal and external coverage in one neck application, reducing handling. They suit homes where flea and intestinal worm risks coexist.

Worm coverage is not identical. Whether heartworm or tapeworm protection is needed depends on regional prevalence and the cat's lifestyle.

Deworming is a medical decision. Kittens, pregnant cats and frail cats especially need a veterinarian to confirm ingredients and frequency; do not stack products on your own.