- FDA has issued an Emergency Use Authorization (EUA) for generic nitenpyram tablets to treat New World screwworm (NWS) infestations in dogs and cats.
- The authorization covers dogs, puppies, cats and kittens that are at least four weeks old and weigh at least two pounds.
- Nitenpyram is the first generic animal drug authorized for use against New World screwworm.
- The treatment is available over the counter and is designed to kill most screwworm larvae within hours of administration.
- FDA officials say the agency has now issued 10 EUAs and three conditional approvals related to New World screwworm response efforts.
- Most dogs and cats in the United States remain at low risk, with elevated concern focused on animals recently located in areas where New World screwworm has been detected.
The U.S. Food and Drug Administration has authorized the emergency use of generic nitenpyram tablets for the treatment of New World screwworm infestations in companion animals, expanding treatment options as federal agencies intensify efforts to contain the destructive parasite.
The Emergency Use Authorization applies to dogs, puppies, cats and kittens that are at least four weeks old and weigh a minimum of two pounds.
According to the FDA, this is the first generic animal drug authorized specifically for the treatment of New World screwworm (NWS) infestations, also known as myiasis.
New Tool in Growing Federal Response
Federal officials characterized the authorization as part of a broader government effort to prevent the spread of New World screwworm within the United States.
“The U.S. government is moving aggressively to contain and eliminate New World screwworm,” said U.S. Health and Human Services Secretary Robert F. Kennedy Jr.
Acting FDA Commissioner Kyle Diamantas noted that the agency has spent months preparing for the parasite’s potential spread and has accelerated reviews of products that may help support response efforts.
According to the FDA, the agency has now issued 10 Emergency Use Authorizations and three conditional approvals related to New World screwworm treatments and control measures.
How the Treatment Works
New World screwworm flies lay eggs in open wounds or mucous membranes of mammals. After hatching, the larvae feed on living tissue, causing significant injury and creating serious animal health concerns.
FDA officials said nitenpyram acts rapidly against the parasite, killing most larvae within hours of the initial dose. Pet owners are instructed to administer a second dose six hours later.
Because the product’s effects are short-lived, it is intended to treat active infestations and does not prevent future infections or protect against reinfestation.
Veterinarians may still need to physically remove remaining larvae following treatment and provide wound management to reduce the risk of infection and additional tissue damage.
Available Without a Prescription
Nitenpyram tablets will be available over the counter in 11.4 mg and 57 mg tablet strengths, with dosing based on animal weight.
The FDA advises that the product should not be administered to dogs or cats weighing less than two pounds. Pet owners are also encouraged to consult a veterinarian regarding appropriate wound care and follow-up treatment.
The product is sponsored by Felix Pharmaceuticals Pvt. Ltd.
Risk Remains Limited for Most Pets
While federal agencies continue preparing for potential spread of New World screwworm, officials emphasized that most dogs and cats in the United States currently face a low risk of infestation.
The greatest concern remains for animals that have recently been located in or traveled through areas where New World screwworm cases have been confirmed.
Information sourced from the U.S. Food and Drug Administration.
