Pharmacotherapeutic group: Anthelmintics, tetrahydropyrimidine. ATC VetCode: QP52AF30.
The product contains three active substances active against roundworms and tapeworms: 1. Febantel, a probenzimidazole, 2. Pyrantel embonate (pamoate) a tetrahydropyrimidine derivative, 3. Praziquantel, a partially hydrogenated pyrazinoisoquinoline derivative.
In this fixed combination product pyrantel and febantel act synergistically against relevant nematodes (ascarids, hookworms and whipworms) in dogs. In particular, the activity spectrum covers Toxocara canis, Toxascaris leonina, Uncinaria stenocephala, Ancylostoma caninum and Trichuris vulpis.
The spectrum of activity of praziquantel covers all important cestode species in dogs, in particular all Taenia spp, Dipylidium caninum, Echinococcus granulosus and Echinococcus multilocularis. Praziquantel acts against adult and immature forms of these parasites.
Praziquantel is very rapidly absorbed and distributed throughout the parasite. Both in vivo and in vitro studies have shown that praziquantel causes severe damage to the parasite integument, resulting in contraction and paralysis. There is an almost instantaneous tetanic contraction of the parasite musculature and a rapid vacuolisation of the syncytial tegument. This rapid contraction has been explained by changes in divalent cation fluxes, especially calcium.
Pyrantel acts as a cholinergic agonist. Its mode of action is to stimulate nicotinic cholinergic receptors of the parasite, induce spastic paralysis and thereby allow removal from the gastrointestinal (GI) system by peristalsis.
Within the mammalian system febantel undergoes ring closure forming fenbendazole and oxfendazole. It is these chemical entities which exert the anthelmintic effect by inhibition of tubulin polymerisation. Formation of microtubules is thereby prevented, resulting in disruption to structures vital to the normal functioning of the helminth. Glucose uptake, in particular, is affected, leading to a depletion in cell ATP. The parasite dies upon exhaustion of its energy reserves, which occurs 2-3 days later.