No, you should **not** apply PetArmor Plus more than once every four weeks (30 days). Applying flea and tick treatments more frequently than directed can lead to a toxic overdose, which can cause serious adverse reactions like skin irritation, tremors, seizures, or even death. If you are still seeing fleas, focus on cleaning your dog's environment and contact your veterinarian for advice on safe, complementary treatments. Never exceed the recommended dosage or frequency.