Heartworm preventatives are considered prescription products by the State Of Alabama. In order for a valid prescription to be written, a licensed veterinarian must examine the patient (Alabama State Practice Act rule 930-x-1-.10. & 930-x-1-.11.), and check their blood to determine a positive or negative status. This means that we can not sell any prescription product including Heartworm preventative unless we have examined your pet and determined it's medical status. We may not sell Heartworm preventative just because you assure us that your pet is taking heartworm preventative. The Veterinarian who examined and tested your pet is the one responsible for filling the prescription through his or her pharmacy. While heartworm preventatives are generally very safe and extremely effective they are not without problems when used improperly. If a patient has microfilaria (immature heartworms in the blood) and is medicated with heartworm preventative, a state of shock could be induced which may lead to death. Some breeds are more sensitive to certain types of preventatives . In some cases I will not recommend topical products for extremely thick coated animals, or pets that do not like being held still for product application. The status of the patient's fecal test can also dramatically effect which product is recommended.

Even more complicating is the situation when a blood smear is negative yet the antigen test is positive for the adult heartworm, the patient has high blood pressure and fluid in the lungs. What should we do now?

These are just a few of the dilemas that veterinarians face with regard to Heartworm Preventatives. It is obvious that this category of products can present an overwhelming set of choices which require a veterinarians advice.