(Merial) NexGard is a beef-flavored, soft, chewable tablet to control flea and tick infestations in dogs. NexGard Chewables contains afoxolaner, which inhibits the central nervous system of fleas and ticks. Kills fleas within 4 hours and ticks within 48 hours post-infestation. Prevents flea and tick infestation for 30 days. NexGard is for dogs 8 weeks of age and older who have weighed at least 4 lbs. for one month. Give orally once per month, at the minimum dosage of 1.14 mg/lb. Chewable tablets make dosing and administration easy and mess-free. Afoxolaner.