: It is illegal for U.S.-based pharmacies to sell Heartgard without a prescription. Sites claiming "no vet RX required" are often operating outside U.S. regulations and may sell unverified or unsafe products.

: Most pet owners buy directly from their primary veterinarian during an annual exam. Clinics like Banfield Pet Hospital also offer online shops for their patients.

: Large retailers like Chewy , 1-800-PetMeds , and Allivet carry Heartgard. When you order from these sites, they will contact your veterinarian to verify the prescription.

: You can often find manufacturer rebates (e.g., $20 back when buying 6 doses) on the NexGard for Pets website or through your veterinarian. Discount platforms like GoodRx also provide coupons and price comparisons for local pharmacies. Frequently Asked Questions - Heartgard Plus