Insects and acarines are exposed to deltamethrin through contact. The mechanism of action is based on a sustained increase in the sodium permeability of the insect’s nerve membranes. This results in hyperactivity followed by paralysis (shock effect), tremor and death of the parasite.

Deltamethrin is slowly and continuously released from the collar into the dog's coat. The active substance spreads from the site of direct contact over the entire skin surface through the lipids and in the hair. Deltamethrin is not absorbed systemically by the host.