Company: NEXAN

FORMULATION: «pour-on» for topical administration.

ACTIVE INGREDIENT(S): Flumethrin: 1% = 10 g/L

CHEMICAL CLASS of the active ingredient(s): Synthetic pyrethroid


PARASITES CONTROLLED* (spectrum of activity)

* Country-specific differences may apply: read the product label.


* Country-specific differences may apply: read the product label.

    • Up to 200 kg: 20 mL product
    • 200 to 300 kg: 30 mL product
    • 301 to 400 kg: 40 mL product
    • Over 400 kg: 50 mL product
  • DEER
    • Up to 6 months: 10 mL product
    • Yearlings and adults: 20 mL product

Read the product label for further details on dosing.


  • LD50 (acute oral) in rats: >2000 mg/kg for the a.i.
    LD50 (acute dermal) in rats: >2000 mg/kg for the a.i.
  • Estimated hazard class according to the WHO: U, unlikely to present acute hazard

Suspected poisoning? Read the article on flumethrin safety in this site.

Withholding periods (=withdrawal times) in days for meat & milk (country-specific differences may apply: read the product label)

  • Meat: New Zealand NIL
  • Milk for human consumption: New Zealand NIL

WARNING !!!: Never use on humans or cats. Synthetic pyrethroids are toxic to cats!

Flumethrin and all synthetic pyrethroids (e.g. cyhalothrin, cypermethrin, deltamethrin, etc.) are extremely toxic to fish and aquatic invertebrates. Do not contaminate dams, streams or waterways with product or used containers. Store original container, tightly closed in a safe place under lock and key.

You may be interested in the following articles in this site dealing with the general safety of veterinary products:


Risk of resistance? LOW

So far there are no reports on resistance of Haemaphysalis ticks to synthetic pyrethroids or other tickicides.

This means that if this product does not achieve the expected efficacy against the mentioned parasites, it is most likely not due to resistance but to incorrect use, which is usually the most frequent cause of product fail

Learn more about resistance and how it develops.


Are the active ingredients of this product ORIGINAL* or GENERICS**?


*Meaning that they are still patent protected and generics are not yet available
**Meaning that they have lost patent protection and may be acquired from manufacturers of generic active ingredients other than the holder of the original patent.

COUNTRIES where this brand/product is marketed: New Zealand
GENERIC BRANDS available? Yes, in some countries. This product itself contains generic flumethrin.

Click here to learn more about GENERIC vs. ORIGINAL drugs.

For an overview on the most used antiparasitic pour-on brands click here.


VETMED FLUMETHRIN Pour on for Cattle & Deer from NEXAN is a classic livestock tickicide containing generic flumethrin.

Flumethrin is a synthetic pyrethroid introduced by BAYER in the 1970s. It is probably the best synthetic pyrethroid against ticks, but less effective against biting flies than other synthetic pyrethroids (e.g. cypermethrin, deltamethrin, etc.). It is still used in many countries (e.g. in Latin America), but the pour-on formulation was withdrawn from the Australian market in the early 2002's because of potential issues with flumethrin residues in beef for export to the USA. Until cattle ticks (Boophilus microplus) resistance to flumethrin became widespread, it was probably the world leading tickicide for cattle. Nowadays it remains a very appreciated product where resistance of cattle ticks is not an issue. It is used mainly in cattle and also in dogs.

All synthetic pyrethroids are veteran pesticides developed in the 1970s-1980s and are basically contact insecticides. This means that when the parasite comes in contact with it (e.g. during the blood meal, after landing on a treated host, etc), the active ingredient that impregnates the host's hair coat penetrates through the cuticle (i.e. the "skin" of insects and other arthropods) into its organism and disturbs essential biological processes in the parasite's body, in this case its nervous system.

After administration to livestock or other animals, synthetic pyrethroids do not have a systemic mode of action, i.e. they are not transmitted to the parasite through the blood or the host. Topically administered synthetic pyrethroids are very poorly absorbed through the skin of the hosts, and what is absorbed is quickly broken down and/or excreted. Consequently the concentration reached in the blood is too low to kill blood-sucking parasites. But this is why they are considered rather safe for mammals, both humans and livestock (cats are an exception: pyrethroids are toxic to them!) and why they leave rather low residues in meat and milk.

All pour-ons containing contact insecticides such as synthetic pyrethroids have the same weakness: they are applied on the back of the animal and spread more or less quickly along the hair coat to other parts of the body, but coverage is usually not homogeneous and some parts of the body are not or only poorly reached. How fast and complete the spreading is depends on a lot of factors (e.g. distance to the delivery point, rain, animal behavior such as grooming, licking, rubbing, etc.) but also on the inert ingredients in the formulation, which may or may not favor spreading. In any case, compared with the backline the concentration of the active ingredient will be significantly lower in body parts that are difficult to reach (e.g. udders, perineum, below the tail, inside the ears, etc), where some parasites may survive because the concentration is not high enough to kill them.

It is useful to know that the active ingredients of many synthetic pyrethroids consist in a mixture of various optical isomers, typically those called "cis", and those called "trans". Flumethrin also consists of a mixture of various optic isomers, but all commercial products contain the same mixture, i.e. this makes no difference in the product quality or efficacy. 


This article IS NOT A PRODUCT LABEL. It offers complementary information that may be useful to veterinary professionals and users that are not familiar with veterinary antiparasitics. 

Information offered in this article has been extracted from publications issued by manufacturers, government agencies (e.g. EMEA, FDA, USDA, etc.) or in the scientific literature. No guarantee is given on its accuracy, integrity, sufficiency, actuality and opportunity, and any liability is denied. Read the site's DISCLAIMER.

In case of doubt contact the manufacturer or a veterinary professional.