Seresto Flea and Tick Collars are for the treatment and prevention of flea and tick infestations for 7 to 8 months. Grey and odour-free, the collar is available in 3 sizes: Seresto Flea and Tick Collar for Cats, Seresto Flea and Tick Collar for Small Dogs and Seresto Flea and Tick Collar for Large Dogs.

Pharmacotherapeutic group:
Ectoparasiticides, insecticides and repellents, pyrethrins and pyrethroids. ATCvet code: QP53AC55 Flumethrin combinations.

Imidacloprid is an ectoparasiticide belonging to the chloronicotinyl group of compounds. Chemically, it can be classified as a chloronicotinyl nitroguanidine. Imidacloprid is active against larval flea stages, adult fleas and lice. Activity against fleas starts immediately after application of the collar. In addition to the indications listed under the section 4.2uses section, an activity against Ctenocephalides canis and Pulex irritans fleas has been demonstrated. Imidacloprid has a high affinity for the nicotinergic acetylcholine receptors in the post-synaptic region of the central nervous system (CNS) of the flea. The ensuing inhibition of cholinergic transmission in insects results in paralysis and death. Due to the weak nature of the interaction with mammalian nicotinergic receptors and the postulated poor penetration through the blood-brain barrier in mammals, it has virtually no effect on the mammalian CNS. Imidacloprid has minimal pharmacological activity in mammals.

Flumethrin is an ectoparasiticide of the synthetic pyrethroid group. According to current knowledge the synthetic pyrethroids interfere with the sodium channel of nerve cell membranes, resulting in a delay in repolarization of the nerve and finally killing of the parasite. In studies on structure-activity relationship of a number of pyrethroids interference with receptors of a certain chiral conformation was noted thereby causing a selective activity on ectoparasites. No anti-cholinesterase activity was noted with these compounds. Flumethrin is responsible for the product’s acaricidal activity. The product provides repellent (anti-feeding) activity against the claimed ticks, thus preventing repelled parasites from taking a blood meal and thereby indirectly aids in the reduction of the risk of Vector-Borne Disease transmission. In addition to the indications listed under ‘Uses’ section, activity has been demonstrated in cats against Ixodes hexagonus and the non-European tick species Amblyomma americanum as well as in dogs against I. hexagonus I. scapularis and the non-European tick species Dermacentor variabilis and the Australian paralysis tick I. holocyclus. The collars were able to improve the Sarcoptes scabiei infestation in pre-infested dogs leading to a full cure after three months.

Cats and Dogs: Both active ingredients are slowly and continuously released in low concentrations from the polymer matrix system of the collar towards the animal. Both actives are present in the cat’s or dog’s haircoat in acaricidal/insecticidal concentrations during the entire efficacy period. The active substances spread from the site of direct contact over the entire skin surface. Target animal overdose and serum kinetic studies have established that imidacloprid reached the systemic circulation transiently while flumethrin was mostly not measurable. Oral absorption of both active substances is not relevant for the clinical efficacy.