Animal & Veterinary

FDA’s Concerns about Unapproved Animal Drugs

As used on this page, the term “unapproved animal drug” refers to a drug intended for use in animals that meets the definition of “new animal drug” in the Federal Food, Drug, and Cosmetic Act but does not have legal marketing status. 

FDA has serious concerns about unapproved animal drugs. These drugs have not been reviewed by FDA and may not meet the agency’s strict standards for safety and effectiveness. Unapproved animal drugs also may not be properly manufactured or properly labeled.

Many unapproved animal drugs are marketed in the United States. Drug companies that make and sell these unapproved animal drugs unfairly compete against drug companies that spend the time and financial resources to obtain what’s called “legal marketing status” for their products. To legally market an animal drug, a drug company must get the drug approved, conditionally approved, or indexed by FDA. Each pathway has different requirements, but they all lead to legal marketing status and provide the benefit of FDA's pre-market review. If the market is full of unapproved animal drugs competing against approved animal drugs, drug companies may be less willing to take one of these pathways. This means that even fewer animal drugs that are reviewed by FDA for safety and effectiveness will be available to veterinarians, pet owners, and animal producers.

Benefit of FDA's Pre-Market Review of Approved Animal Drugs

Knowing a drug is safe, effective, and high-quality is the benefit of FDA’s drug approval process. The agency rigorously evaluates an animal drug before approving it. As part of the approval process, the drug company must prove to FDA that:

  • The drug is safe and effective for a specific use in a specific animal species. If the drug is for use in food-producing animals, the drug company must also prove that food made from animals treated with the drug is safe for people to eat;
  • The manufacturing process is adequate to preserve the drug’s identity, strength, quality, and purity. The drug company must show that the drug can be consistently produced from batch to batch; and
  • The labeling is truthful, complete, and not misleading. The drug company must make sure that the labeling contains all necessary information to use the drug safely and effectively and includes the risks associated with the drug.

Continued FDA Monitoring of Approved Animal Drugs

FDA’s role does not stop after the agency approves an animal drug. As long as the drug company markets the animal drug, the agency continues to monitor:

  • The drug's safety and effectiveness. Sometimes, the agency’s post-approval monitoring uncovers safety and effectiveness issues that were unknown at the time of approval;
  • The manufacturing process to ensure quality and consistency are maintained from batch to batch;
  • The drug's labeling to make sure the information remains truthful, complete, and not misleading; and
  • The company’s marketing communications related to the drug to make sure the information is truthful and not misleading.

Required Reporting of Problems with Approved Animal Drugs

As part of FDA’s continued monitoring of safety and effectiveness, a drug company that makes and sells an approved animal drug is required to report to FDA all problems that occur with the drug after it's on the market. Problems include adverse drug experiences and product defects. An adverse drug experience is an undesired side effect associated with the drug or a lack of effect (the drug doesn't do what it's expected to do). Adverse drug experiences also include unfavorable reactions in people who handle the drug. Product defects are problems such as defective packaging or an abnormal appearance of the drug. The required reporting of adverse drug experiences and product defects allows FDA to more easily identify and correct problems with approved animal drugs.

For more information about reporting adverse drug experiences, please visit the following website:

How to Report Animal Drug Side Effects and Product Problems

Risk of No FDA Review and Monitoring

Because unapproved animal drugs don’t go through FDA's pre-market review, veterinarians, pet owners, and animal producers have no way to know if these drugs are safe and effective or if their manufacturing processes are adequate to maintain quality and consistency from batch to batch. Also, because drug companies aren’t required to report adverse drug experiences and product defects for unapproved animal drugs to FDA, problems with these drugs may be slow to be identified.

By bypassing FDA’s drug approval process, drug companies that make and sell unapproved animal drugs potentially put the health of animals and people at risk.

Page Last Updated: 03/26/2018
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