When cattle need a lice treatment, the pour-on you reach for decides how much goes on each animal, how often you can repeat it and how long before slaughter. This guide compares the three cattle pour-ons we carry that list lice on their Canadian labels: Lice-Away and BackLine, which are permethrin insecticides registered under the Pest Control Products Act, and Bimectin Pour-On, an ivermectin veterinary drug. Everything here comes from the current labels. Your veterinarian is the right person for a lice-control plan for your herd.
Two kinds of product
Lice-Away Pour-On Insecticide (PCP Reg. No. 23777.02) and BackLine Pour On Insecticide (PCP Reg. No. 31712) are pesticides, both registered to Engage Animal Health Corporation, both with permethrin as the active ingredient, and both marked "Agricultural" on the label.
Bimectin Pour-On (DIN 02283123) is a non-prescription veterinary drug with ivermectin as its medicinal ingredient. Its label lists lice along with roundworms, lungworms, grubs, mites and hornflies. We cover it in detail in our guide Bimectin Pour-On for Cattle: Dose, Withdrawal and Rain, from the Canadian Label.
What each label covers
Lice-Away: "Controls biting lice and horn flies and as an aid in the control of sucking lice on beef cattle and lactating and non-lactating dairy cattle." The guarantee is permethrin 1.0%, and the label says it is ready to use: "DO NOT dilute."
BackLine: "Controls biting lice, sucking lice, horn flies and Rocky Mountain wood ticks (Dermacentor andersoni) on beef cattle and lactating and non-lactating cattle." The guarantee is "Permethrin 5.0% w/w." For ticks, the label says to "apply topically at time of entry into tick infested pastures."
Both permethrin labels say "DO NOT use on any other animal." Bimectin's label says it "is formulated for external use only in cattle; it should not be used in other species."
How much per animal
The three labels set very different rates:
- Lice-Away: "Apply 15 mL (0.5 fl. oz) per 45 kg (100 lbs) body weight up to a maximum of 150 mL (5 fl. oz) for one animal."
- BackLine: "Apply 3 mL (0.1 fl. oz) per 45 kg (100 lbs) body weight up to a maximum of 30 mL (1 fl. oz) for one animal."
- Bimectin Pour-On: 1 mL per 10 kg of body weight, along the top-line from the withers to the tail head.
Both permethrin labels say to pour "along the back and down the face taking care to avoid the eyes, nose and mouth", and both allow the face to be done with a cloth slightly moistened with the product instead.
Worked from those rates (our arithmetic, not a label table): on both permethrin labels an animal of about 450 kg reaches the per-animal maximum, 150 mL of Lice-Away or 30 mL of BackLine. A 4 L jug therefore covers about 26 mature animals at the Lice-Away maximum and about 133 at the BackLine maximum. Bimectin has no per-animal cap on its label; a 600 kg cow takes 60 mL.
How often you can repeat it
The two permethrin labels use the same wording: "DO NOT repeat treatment for at least 14 days." "Treatment must only be repeated after 14 days if pest problem persists or reoccurs." "DO NOT apply more than 2 applications/animal/year." The Lice-Away label adds: "For control of lice, two treatments 14 days apart are recommended."
So with either permethrin pour-on, a lice program that uses two treatments 14 days apart uses up that animal's two applications for the year. Plan the timing with that in mind.
Bimectin's label does not set a repeat interval in the same way; it lists, in a "Persistent Effect" section, how long after treatment it says certain parasites are controlled, and it asks you to consult your veterinarian on timing.
Slaughter and dairy
- Lice-Away and BackLine: "Leave a one day interval between last application and slaughter."
- Bimectin Pour-On: "Treated cattle must not be slaughtered for use in human food for at least forty-nine (49) days after the latest treatment with this drug."
For dairy, both permethrin labels say: "For Dairy Cattle, DO NOT use this product in combination with any other permethrin treatment." Bimectin's label says: "Because a withholding time for milk has not been established, do not use in dairy cows twenty (20) months of age or older."
Handling and storage
Lice-Away's label precautions include "Harmful if swallowed, inhaled, absorbed through skin" and call for "long pants, long-sleeved shirt, chemical-resistant gloves, shoes, and socks during mixing, loading, application, clean-up and repair." BackLine's label says "CAUTION: SKIN IRRITANT." and calls for "long pants, long-sleeved shirt, chemical-resistant gloves, shoes and socks during application and clean-up." BackLine's storage directions include "Protect from freezing."
Both permethrin labels warn about water: Lice-Away says it is "Highly toxic to aquatic organisms", and BackLine that it "is very toxic to aquatic organisms." Keep rinse water and empty jugs away from dugouts, sloughs and creeks, and follow each label's disposal directions.
Which one fits
That depends on your herd, the time of year and what else you are treating for, which is a conversation for your veterinarian. What the labels do settle: the permethrin pour-ons have a one-day slaughter interval and a two-application yearly limit; BackLine is the only one of the three whose label names Rocky Mountain wood ticks; and Bimectin also covers internal parasites, with a 49-day slaughter withdrawal.
Where to find them
We carry Lice-Away Pour-On Insecticide 4 L, BackLine Pour-On 4 L, and Bimectin Pour-On 5 L and 20 L, with the rest of our cattle dewormers and parasite control range. Pesticides are regulated by Health Canada; read and follow the label before every use.
Deworming for internal parasites only? The Safe-Guard Suspension label lists no external parasites; our guide Safe-Guard for Cattle: Fenbendazole Dose, Withdrawal and the Canadian Label reads that label, and Bimectin Pour-On for Cattle: Dose, Withdrawal and Rain, from the Canadian Label covers the pour-on in full.
Sources: Health Canada Pesticide Label Search, labels for LICE-AWAY POUR-ON INSECTICIDE (PCP Reg. No. 23777.02) and BACKLINE POUR ON INSECTICIDE (PCP Reg. No. 31712), Engage Animal Health Corporation, both dated 2025-08-01, viewed October 2026; Health Canada Drug Product Database, BIMECTIN (IVERMECTIN) POUR-ON FOR CATTLE (DIN 02283123); the Bimectin Pour-On Canadian label (8BIM212-210), as reproduced on drugs.com (Animalytix, updated 2026-05-28), viewed October 2026.