A veterinarian must confirm your pet's current heartworm status via a blood test before starting or renewing a prescription.
Avoid sites that claim "no prescription required" for U.S. customers. Buying from unverified sources carries significant risks: How to Avoid the Disasters of Counterfeit Pet Prescriptions
Buying heartworm prevention online is a convenient way to save money and stay consistent with your pet's health, but it requires careful navigation to ensure safety and legality. In the United States, from a licensed veterinarian. 1. The Legal Requirement: Why You Need a Prescription
You cannot legally buy legitimate heartworm prevention in the U.S. without a vet’s authorization. This regulation exists because:
Visit your vet for an annual blood test.
