Comfortis is a monthly chewable tablet that protects your cat from fleas. Comfortis starts to work within 30 minutes of administration, and kills all fleas within 4 hours for dogs. For cats it kills 90percent of fleas within 2 hours and 100 percent within 24 hours. Comfortis remains active for a month after treatment, preventing your pet from becoming re-infested, and is so effective at killing fleas that it can also be used to control flea allergy dermatitis. Safe for use in puppies and kittens from 14 weeks of age. Consult your veterinarian prior to using Comfortis to treat pregnant and lactating animals or pets with pre-existing epilepsy. Comfortis should be given with a meal.