Farmers rely on pharmaceuticals such as antibiotics to treat sick or injured cows, and maintaining a quality client-patient relationship with your veterinarian is critical. The better they understand you and your herd, the more they can treat illnesses accordingly. Currently, there are four classes of veterinary drugs: prescription (Rx), over-the-counter (OTC), veterinary feed directive (VFD), and unapproved products. Rx, OTC, and VFDs are all approved by the U.S. Federal Drug Administration (FDA).
What is ELDU?
In an Iowa State University Dairy Extension webinar, Allison Vander Plaats, D.V.M., explained extra-label drug use (ELDU), its limitations, and concerns that come along with it. Vander Plaats defined ELDU as using drugs for indications not mentioned in the label, at a different dose, route, or frequency that is not indicated on the label. Under the American Medicinal Drug Use Clarification Act (AMDUCA) of 1994, veterinarians are allowed to use drugs that have been FDA approved for extra-label indications following certain guidelines. These limitations allow drug usage only if “treatment will prevent suffering or death, if no drugs are labeled for such use, labeled drugs have proved to be ineffective, or the drug is unavailable in required concentration,” Vander Plaats explained. She emphasized that ELDU should be used as a last resort. If used, it is important to note that withdrawal times must be extended.
Determining if a drug is FDA approved
Since 2018, all veterinary prescriptions, including over-the-counter and veterinary feed directives, are labeled with a new animal drug application (NADA) or approved new animal drug application (ANADA) number. This number can be found on the outer packaging, the paper insert, or on the bottle. Looking for this number makes it easy for users to determine if it is an FDA approved drug. For example, Banamine is marked as approved by FDA under NADA #101-479 on the label. If unsure, the U.S. Food and Drug administration website has an online database of every approved animal drug, making it easy to search for what you’re looking for.
Vander Plaats recommended using the American Association of Swine Vets (AASV) interactive exercise to determine whether or not to use a drug for extra-label use by answering a set of questions. She encouraged follow-up testing to make sure the AASV’s predictions are correct.
Restrictions and concerns
Highly pathogenic avian influenza (HPAI) has been on the rise in recent years in dairy cattle and other animal species. Symptoms in dairy cattle include a high fever of up to 107°F, drop in milk production, lower rumination, diarrhea, and thick brown or yellow milk. These symptoms can cause severe dehydration. Vander Plaats explained the two treatments used for HPAI in dairy cattle has included fluid therapy or, in some cases, aspirin. Many herds have been resorting to aspirin when fluid therapy is ineffective.
Vander Plaats encouraged farmers to read drug labels and spend time understanding what each one means. It helps in understanding each drug’s purpose, limitations, and restrictions, such as if it can be used for ELUD. Following procedure and rules are key for staying in compliance when managing dairy cattle, striking the balance of animal care in food animal production.
