Sentinel Spectrum Medium Yellow is an effective medication for the treatment and prevention of fleas, external and internal parasites in medium dogs from 11-22kg. These tasty beef-flavoured chewable tablets can be administered monthly to provide your dog with 30-day long protection against fleas, heartworms and intestinal worms. The innovative formula of Sentinel Spectrum interferes with the nerve transmission of external parasites, effectively eliminating and protecting against heartworms, roundworms, hookworms and whipworms, as well as all intestinal forms of tapeworm. In addition, the active ingredient Lufenuron interrupts the flea life cycle and prevents flea larvae and eggs from entering the adult stage. Treatment for heartworm is dangerous and expensive, so prevention is essential. Sentinel Spectrum is a highly effective preventative treatment. Protect your dog with Sentinel Spectrum Medium Yellow! With Sentinel Spectrum getting rid of fleas and other parasites, your dog's environment is safe and your dog is healthier and happier than ever! Sentinel Spectrum Medium Yellow is safe to use in puppies from 6 weeks, as well as pregnant and lactating females. Looking for some treats to encourage and reward your dog for taking his or her medication? Check out our range of gourmet dog treats here!