Product choices

Choosing the right product to treat worms and getting the most from it are key factors, not only in the fight against anthelmintic resistance but also in ensuring optimum sheep performance at least cost.

Use the SCOPS ‘Know Your Anthelmintics Groups’ Guide for accurate, easy-to-use information on the products available in the various chemical groups and the parasites they control. Also see this AHDB 'Choosing the right product' video.

These top tips will help you get the most out of an anthelmintic every time you use it:-

  • Choose the right product. Targeting the parasite(s) correctly means better results and reduces the risk you will need to treat again. (SCOPS Technical Manual. Chapter 2.5)
  • Source a narrow spectrum product where appropriate, which will reduce selection for resistance to the broad spectrum groups. 
  • Use combination products only when they are necessary. Are you sure your animals need treating for both worms and fluke, for example, or would a product that just treats for one or the other a better choice? Off target use can accelerate the development of anthelmintic resistance. (SCOPS Technical Manual. Chapter 4.2)
  • Administer anthelmintics effectively and handle and store them correctly. Find out more at   
  • Never mix anthelmintics with each other or any other product prior to administration.
  • Check the product has been effective by carrying out a simple drench test. Resistance sneaks up on you and this will give you early warning. It will also make sure you are using an effective product that gives good worm control. Find out more at