'Drench' is the common term for anthelmintic. These are products that contain a chemical or chemicals that kill the target worms. Drenches can be classified according to their active ingredients (chemical), how many types of worms they target ('broad-spectrum' or 'narrow spectrum') and whether they are short or long acting.

There can also be different active ingredients within the same chemical group of drenches. Notably, the macrocyclic lactone (ML) group contains the different actives - ivermectin, abamectin and moxidectin. To have an effective worm management program, you must know which drenches are effective against which worms on your property through a drench resistance test.

WormBoss has arranged the drenches according to what they do, that is, broad or narrow spectrum and long acting or short acting.  The list also indicates if a drench group has any specific characteristics such as the period of activity and against which worms.