Why do I need a prescription?
June 27th, 2013
When you are given a prescription for a medication for your pet, it means that your veterinarian has made a decision that the medication is recommended or necessary to treat your pet's health problem. Many prescription drugs are only effective for specific problems, and may actually be harmful to your pet if used without that critical veterinary examination and diagnosis. Having these drugs available as prescription-only medications ensures that they are used appropriately.
Let's take heartworm preventives as an example. Heartworm preventives are labeled as "prescription-only" because it's critical that your veterinarian makes sure the medication is the right one based on your pet's health status. The preventives target the microfilaria, which are the larvae of heartworms that circulate in the blood and eventually become adult heartworms. If your dog (or cat) has heartworms, giving the preventive medication will not effectively treat the disease because the preventives don't readily kill adult heartworms, and it could potentially cause a life-threatening reaction if your pet has a large number of microfilaria circulating in its bloodstream.
There are drugs, called "over the counter" (OTC) drugs, that don't require prescriptions. Drugs can be bought OTC when the Food and Drug Administration (FDA) determines that the directions for the drug's use aren't overly complicated and are adequate for the public to follow. In some cases, such as the common headache medications for people, the OTC version is just a weaker strength than the prescription form. However, in many cases, a medication is only available with a prescription for the reasons we mention above.