- The FDA issued an Emergency Use Authorization (EUA) for Bimectin (ivermectin) injection to prevent New World screwworm (NWS) myiasis in certain cattle.
- The product may be administered within 24 hours of birth, at castration or when a wound appears, according to the authorization.
- Bimectin is a generic version of Ivomec, which received an EUA for NWS prevention in cattle in February 2026.
- The injectable product is available over the counter but is not authorized for lactating dairy cows or calves intended for veal production.
- Producers must observe a 35-day slaughter withdrawal period.
- The authorization marks the FDA’s 14th EUA related to New World screwworm.
The U.S. Food and Drug Administration has expanded the options available to cattle producers for preventing New World screwworm infestations, issuing an Emergency Use Authorization for Bimectin (ivermectin) injection.
Under the EUA, Bimectin may be used to prevent New World screwworm myiasis in cattle when administered within 24 hours of birth, at the time of castration or when a wound appears.
The FDA said the authorization is part of federal efforts to protect U.S. agriculture from the threat posed by New World screwworm.
“This authorization reflects the FDA’s commitment to expanding generic drug options against New World screwworm,” Timothy Schell, Ph.D., director of the FDA’s Center for Veterinary Medicine, said in the announcement. Schell said making both generic and pioneer products available can help prevent producers from being dependent on a single manufacturer or product.
Food safety restrictions apply
Bimectin injection is not authorized for use in lactating dairy cows or calves that will be processed for veal.
The FDA also emphasized that producers must follow the product’s 35-day slaughter withdrawal period to help prevent drug residues from entering the food supply.
According to the agency, the available scientific evidence supports a reasonable belief that Bimectin injection may be effective in preventing NWS myiasis in certain cattle when used under the conditions of the EUA. The FDA also determined that the product’s known and potential benefits outweigh its known and potential risks when used as authorized.
Generic alternative to previously authorized product
Bimectin injection is a generic version of Ivomec, an ivermectin product the FDA authorized in February 2026 for the prevention of New World screwworm myiasis in cattle.
Bimectin injection was already FDA-approved for the treatment and control of several parasites in cattle. The new emergency authorization applies specifically to the injectable formulation and does not extend to other Bimectin dosage forms.
The product is available over the counter without a prescription. Cattle producers are responsible for administering it in accordance with the authorized labeling and FDA fact sheet.
The Bimectin authorization is the FDA’s 14th EUA issued in response to the New World screwworm threat.
Information sourced from the U.S. Food and Drug Administration’s press release.
