Advocate (Advantage Multi) flea and heartworm Spot-on For Large Dogs 22-55 lbs (10-25 kg) - No Rx requiredAdvocate (Advantage Multi) for Large Dogs from 22 55 lbs (10 25 kg) Kills fleas on dogs and prevents infestations for at least weeks Kills fleas before they can lay eggs Kills flea larvae in the dog surroundings Assists in the control of flea allergy dermatitis in dogs. Treatment of ear mite infestation (Otodectes cynotis), Sarcoptic mange (caused by sarcoptes scabiei var. canis) demodectic mange (caused by demodex canis) Treatment of biting lice