If your dog weighs 45 to 88 pounds, then buy the 45-88 lb. box. The 45-88 lb. box comes with three 2.68 applicators. If your dog weighs 23 to 44 pounds, then buy the 23-44 lb. box. The 23-44 lb. box comes with three 1.34ml applicators. FRONTLINE Plus also contains an important addition of (S)-methoprene which works to prevent the multiplication of fleas by killing fleas in their immature stages (eggs, larvae and pupae).

This article was co-authored by Pippa Elliott, MRCVS. Dr. Elliott, BVMS, MRCVS is a veterinarian with over 30 years of experience in veterinary surgery and companion animal practice. She graduated from the University of Glasgow in 1987 with a degree in veterinary medicine and surgery. She has worked at the same animal clinic in her hometown for over 20 years. Bathing/shampooing/water exposure does not affect the efficacy of the product as long as it doesn’t occur more than once a week. FRONTLINE Plus® is a veterinary medicine with a robust safety profile. It can be applied to cats from 8 weeks of age that weigh at least 1 kg and ferrets from 6 months of age. It can also be used on cats in pregnancy.Bathing/shampooing/water exposure does not affect the efficacy of the product as long as it does not occur more than once a week. FRONTLINE PLUS ®, FRONTLINE TRI-ACT ® and FRONTLINE ® SPOT ON kill fleas by affecting their nervous system, making them hyperactive before dying. These dying fleas often rise to the top of the pet’s coat and bounce, so if you see fleas after treatment, it’s often a sign the product has got to work. Find out more about why you may still see fleas after treating your pet. FRONTLINE Plus® is a veterinary medicine with a robust safety profile. It can be applied to dogs from 8 weeks of age that weigh at least 2 kg. It can also be used in pregnant and lactating bitches. Calculate your dog’s weight. Subtract your weight from the total weight, i.e., the weight of you and your dog together. The resulting number is your dog’s weight. [4] X Research source

Weigh yourself. To determine the correct Frontline Plus dosage, you will need to establish your dog’s weight. To determine your dog’s weight, you will need to weigh yourself first. [2] X Research source