Q: Why are some spot-on flea and tick preventive medications only available through my veterinarian?
A: Some manufacturers have decided to sell their products only through veterinarians so that the veterinarian and pet owner can discuss the situation and work together to determine the best flea and tick treatment for that pet. It's not that the product is "prescription-only" – it's that the manufacturer believes the product should only be sold through veterinarians. In addition, it seems more likely that the product will be used properly (for example, a cat won't be treated with a product labeled only for use in dogs) if the veterinarian is supplying the medication and is counseling the pet owner on the proper use of the medication.
If the spot-on flea and tick product is also labeled for heartworm prevention, it is only available through your veterinarian for the reason we previously described – it is critical that your veterinarian checks for a heartworm infection before your pet is given a heartworm preventive medication.