A complete and balanced dry dog food for large size adult dogs. PRO PLAN Large Adult with OPTILIFE is a complete and balanced dry dog food for large size adult dogs. OPTILIFE has been developed by vets and nutritionists at PURINA to give your large-sized breed dog the best nutrients for their health needs. It contains specific nutrients balanced at optimum levels that will help keep them in good condition. Formulated for large dogs, OPTILIFE ensures your dog absorbs all the key elements of their food, as well as looking after their teeth and joints.