extra label drug use in food animals

what is extra-label drug use?

use of a drug in a manner other than that listed on its label

what is extra-label drug used governed by?

the animal medicinal drug use clarification act (AMDUCA)

what are the requirements to use drugs in an extra label manner?

1. valid veterinarian/client/patient/relationship (VCPR)

2. must be for therapeutic use only

3. a careful diagnosis of the condition has been made

4. determination is made that there is no other drug in the market that could be used for the diagnosed condition

5. significantly extended time period is assigned for drug withdrawal prior to marketing meat or milk and steps are taken to ensure withdrawal period is met

6. procedures are instituted to assure that the identity of treated animals is adequately maintained

7. all drugs dispensed to the producer by veterinarian bear label information which is adequate to assure proper use of the product

8. extra label use drug of feed additives is not permitted under any circumstances

what makes a valid veterinarian/client/patient/relationship (VCPR)

• veterinarian has assumed responsibility for making clinical judgements regarding the health of the animal and the need for medical treatment and the client has agreed to follow the vet’s instructions

• vet has sufficient knowledge of animal to initiate at least a preliminary diagnosis of the medical condition of the animal - which means the vet has seen and is personally acquainted with the keeping and care of the animal in the manner of annual exam visits

• vet is readily available for follow-up evaluation or has arranged emergency coverage in case pt suffers from adverse reactions

what are the FDA drug classifications?

1. over the counter drugs

2. veterinary prescription drugs

3. veterinary feed directive

what are over the counter drugs?

drugs that can be purchased and used without veterinary supervision

T/F - over the counter drugs can be used however you want.

false - over the counter drugs must be used as they’re instructed otherwise its consider extra label use

what are veterinary prescription drugs?

drug that requires supervision by a licensed veterinarian

what 2 things are required for prescription veterinary drugs to be prescribed?

1. a valid vet-client-patient relationship

2. a statement that reads

• CAUTION: federal law restricts this drug to use by or on the order of a licensed veterinarian

do antimicrobials delivered via water require a veterinary prescription?

yes - antimicrobial resistance

what are veterinary feed directives?

governs how antimicrobials are used in feed and states that inclusion of antimicrobials at sub-therapeutic levels in feed is prohibited

what are feed mills required to obtain in order to mix feed-grade antimicrobials into rations?

require oversight of a licensed vet in the form of a VFD request

what antimicrobials do not require a veterinary feed directive (VFD)?

• BMD (bacitracin methylene disalicylate)

• denagard (tiamulin)

• flavomycin (bambermycin)

• mecadox (carbadox)

• skycis (narasin = rumensin, ionophore fed to cattle, pigs)

what is the definition of drug compounding?

alteration of approved drugs to obtain a therapeutic product

who is allowed to compound drugs?

• licensed pharmacist

• licensed veterinarian

when is compounding illegal?

if an approved animal drug is available that is comparable to the compounded preparation

what drugs cannot be used extra-label in food animals under any circumstances? explain why they cannot be used.

1. diethylstilbestrol - potent repro carcinogen

2. chloramphenicol - can be toxic to bone marrow/aplastic anemia

3. nitroimidazoles/nitrofurans - carcinogen concerns

4. clenbuterol - can cause tachycardia and death

5. dipyrone - depresses white blood cell production in bone marrow/myelotoxicity)

6. fluoroquinolones - used in poultry assumed to induce salmonella resistance (approved for cattle + pigs)

7. glycopeptides - one of only 2 drugs for treating resistant staphylococcus (MRSA) and clostridial (C. diff.) infections in humans

8. medicated feeds - no extra label privileges ever

9. cephalosporins - requires that dosing instructions on the label be followed in call cases

10. adamantanes, neuraminidase inhibitors - influenza antiviral drugs, misuse of adamantanes has led to resistance worldwide

11. DMSO, fluroquinolones, phenylbutazone, sulfa drugs - drugs with very limited use or no approval for use in dairy cows

12. aspirin - used to treat dairy cows with bird flu but that was never approved by FDA

what items are required by law on a veterinary prescription label?

• name, address, and telephone number of veterinarians

• name of clients

• identification of animal(s) treated, species and numbers of animals treated, when possible

• date of treatment, prescribing, or dispensing of drug

• name, active ingredient, and quantity of the drug (or drug preparation) to be prescribed or dispensed

• drug strength (if more than one strength available)

• dosage and duration

• route of administration

• number of refills

• cautionary statements, as needed

• expiration date if applicable

• slaughter withdrawal and/or milk withholding times, if applicable