The active ingredient, nitenpyram belongs to the chemical class of neonicotinoids which bind and inhibit insect specific nicotinic acetylcholine receptors. Nitenpyram interferes with nerve transmission and leads to the death of adult fleas. Nitenpyram does not inhibit acetylcholinesterase.

Effects on fleas (Ctenocephalides felis) may be seen as soon as 15-30 minutes after administration of the product to the host animal. This coincides with the first blood meal taken by fleas after sufficient blood levels are reached. Between 95% and 100% efficacy is observed within the first 6 hours and 100% efficacy is reached within 24 hours with no residual activity.

Nitenpyram is rapidly and to over 90% absorbed from the gastrointestinal tract of cats and dogs. Feeding does not affect absorption in dogs. Feeding slightly delays Tmax in cats without affecting the other pharmacokinetic properties and without affecting efficacy. The maximum blood concentration is reached after 0.5 to 2 hours in both fasted target species and the elimination half-life is about 4 hours in dogs and 8 hours in cats. More than 90% is eliminated in the urine within 1 day in dogs and 2 days in cats, mainly as the unchanged molecule.