: Dogs must test negative for heartworms before starting.
🚩 : Avoid websites claiming to sell Trifexis without a prescription. These products may be counterfeit , expired, or unsafe for your pet. can i buy trifexis over the counter
Federal law restricts this drug to use by or on the order of a . 🩺 Why a Prescription is Necessary : Dogs must test negative for heartworms before starting