Treating monthly with PURINA TOTAL CARE Tasty Chew Heartwormer & Allwormer for Small Dogs will prevent heartworm infection and control adult roundworm, immature roundworm, adult whipworm, adult hookworm, adult tapeworm, and aid in the control of adult hookworm infection. Units in pack: 3 x Chews Dosage: Once a month Suitable for: Small dogs and puppies 4 to 11 kg in bodyweight Not recommended for: Puppies less than 2 weeks old