A new era in cattle parasite protection.

EXZOLT™ Cattle-CA1 (fluralaner topical solution) is conditionally approved by the FDA for the:
• Prevention and treatment of infestations caused by New World screwworm (Cochliomyia hominivorax) larvae (myiasis)
• Treatment and control of cattle fever tick (Rhipicephalus microplus)

EXZOLT™ Cattle-CA1-CA1 offers proven efficacy of fluralaner as a new option against these potentially deadly parasites. It signals a long-awaited breakthrough for the livestock industry that has watched New World screwworm flies moving north in Mexico toward U.S. borders.

The prescription product is now available. Use only as directed on the label.

Read the Announcement

Innovative product with a new molecule.

EXZOLT™ Cattle-CA1 (fluralaner topical solution) delivers a powerful new tool to protect cattle against deadly parasites. Fluralaner, the active ingredient, represents a breakthrough in parasite management as the  first isoxazoline-class ectoparasiticide for use in U.S. beef cattle.

With a novel mode of action and no known resistance, EXZOLT Cattle-CA1 delivers fast-acting protection.

EXZOLT™ Cattle-CA1 received FDA conditional approval based on a reasonable expectation of effectiveness, supported by published studies and Merck Animal Health research. The active ingredient, fluralaner, has demonstrated safety and efficacy across species in over 170 global clinical studies and is approved in 93 markets.

Learn More

Frequently Asked Questions

What does conditional approval mean?

EXZOLT™ Cattle-CA1 is conditionally approved by the FDA pending completion and approval of all efficacy data. EXZOLT™  Cattle-CA1 has a reasonable expectation of effectiveness in cattle based on published studies and Merck Animal Health research.

Is Merck Animal Health taking steps for full approval?

Yes. Conditional approval lasts one year and can be renewed annually for up to five years. To renew, Merck Animal Health must show progress toward proving full effectiveness. The company is actively conducting research and submitting data to the FDA.

Can it be used off-label?

Off-label use is prohibited. It is a violation of Federal Law to use EXZOLT™ Cattle-CA1 other than as directed in the labeling.

What should I do if I suspect New World screwworm or cattle  fever tick?

Contact your veterinarian immediately. Suspected cases must be reported to APHIS and state animal health officials.  Visit www.aphis.usda.gov for reporting procedures.

Is there research on fluralaner in cattle?

Backed by over 170 global clinical research studies, fluralaner has demonstrated safety and efficacy across species. Fluralaner products, which include Bravecto® (fluralaner) Chews, Bravecto® Topical (fluralaner topical solution) and Bravecto® 1-Month (fluralaner), are approved in 93 markets with over 270 million doses distributed worldwide across species. The first countries  with approvals for use of fluralaner in cattle are Brazil, Mexico and Australia. Adverse events for fluralaner are rare, based on  global reporting.

How do you administer EXZOLT™ Cattle-CA1?

Administer as a pour-on at 1 mL per 44 pounds of body weight, applied along the dorsal midline from withers to the base of the tailhead. Add 2.5 mL for each 110 pounds above 1,320 pounds of body weight. For the 1 L presentation, squeeze the product into the dosing chamber to measure total volume needed. For the 5 L presentation, use the provided dosing gun.

When should EXZOLT™ Cattle-CA1 be administered?

Product use should be discussed with your veterinarian. This product is only available as a prescription from your veterinarian.
New World screwworm:
• Treatment: Apply under your veterinarian’s guidance for active infestations.
• Prevention: Use immediately at wound creation (e.g., castration, dehorning).

Cattle fever tick:
• Treatment & Control: Apply to new arrivals under your veterinarian’s guidance.

How does it work?

Fluralaner targets the nervous systems of these parasites, effectively killing them and protecting cattle from infestation.

What precautions should be taken when administering to cattle?

Wear protective gloves, long sleeve shirts, pants and avoid skin and eye exposure during handling. This product can be flammable. Keep the product away from extreme heat or open flame, including branding irons.

What is the slaughter withdrawal period?

Cattle must not be slaughtered for human consumption within 98 days of treatment. If cattle are continuously exposed to temperatures at or above 60° F after product administration, then cattle may be slaughtered for human consumption 44 days after treatment. Violative residues may result if cattle are exposed to temperatures below 60° F after administration and are slaughtered at 44 days. For complete safety information and product dosing instructions, refer to the product label.

Can this product be given to lactating dairy cows?

Not for use in female dairy cattle 20 months of age or older, including dry dairy cows; use in these cattle may cause drug residues  in milk, and or calves born to these cows or heifers.

Will parasites develop resistance to EXZOLT™ Cattle-CA1?

Currently, no resistance is known. A comprehensive parasite control strategy helps delay resistance.

How should I store the product?

Store in original packaging at room temperature (59–86°F), away from sunlight, children and pets. After opening, use within 6 months.

Does it control horn flies?

EXZOLT CATTLE CA-1 is only approved for treatment and control of cattle fever tick and treatment and prevention of New World screwworm myiasis.

Can it be used on wildlife, goats and sheep?

EXZOLT™ CATTLE CA-1 is only approved for the use in cattle.

Does it control lice?

It is only approved for treatment and control of cattle fever tick and treatment and prevention of New World screwworm myiasis.

Can it be used on breeding bulls?

Not for use in bulls intended for breeding over 1 year of age, as reproductive safety has not been evaluated.

What special personal protective equipment (PPE) should be used when handling or applying the product?

Personal protective equipment should be worn, such as gloves, long sleeve shirt and pants, as well as glasses or goggles, while handling the product.

How quickly should I use the product after opening the container?

Use within 6 months after first opening.

Can it be given to calves younger than 2 months of age?

The product has not been tested for use with calves younger than 2 months of age.

Will it work for other ticks in the U.S.?

EXZOLT™ Cattle-CA1 is only approved for treatment and control of cattle fever tick and treatment and prevention of New World screwworm myiasis.

EXZOLT™ Cattle-CA1:  Easy to apply and dose

The prescription product is administered as a pour-on.
It circulates in the bloodstream, and breaks the lifecycle of the
parasites, defending cattle against infestations. The pre-calibrated packaging helps ensure the right dose is given every time. The 1 L bottle design allows for proper topical application along the animal’s back. The  5 L is administered with an EXZOLT™ Cattle-CA1 applicator. The blue-colored solution makes it simple to accurately and quickly measure the dose volume for each animal.

Read Label

Important Safety Information

Not for use in humans. Keep out of reach of children. Accidental exposure may cause skin and eye irritation. Highly flammable. Keep away from heat, sparks, open flame or other sources of ignition. Use only for the prevention and treatment of infestations caused by New World screwworm (Cochliomyia hominivorax) larvae (myiasis) and treatment and control of cattle fever tick (Rhipicephalus microplus) in beef cattle 2 months of age and older and replacement dairy heifers less than 20 months of age. Not for use in bulls intended for breeding 1 year of age and older, dairy calves, and veal calves. Cattle must not be slaughtered for human consumption within 98 days of treatment. If cattle are continuously exposed to temperatures at or above 60° F after product administration, then cattle may be slaughtered for human consumption 44 days after treatment. Violative residues may result if cattle are exposed to temperatures below 60° F after administration and are slaughtered at 44 days. For complete safety information and product dosing instructions, refer to the product label.