123997-26-2

Crystalline Solid

A mixture of Eprinomectin B1a and B1b showing anti-anthelintic activity

A mixture of semi-synthetic Avermectins; containing 90% or more of component B1a and 10% or less of component B1b. Antiparasitic

Eprinomectin is a mixture of eprinomectins B1a and B1b in a 9:1 ratio, produced from a mixture of avermectin B1a and B1b. Eprinomectin is used commercially as a topical endectocide (insecticide, miticide and nematocide) for cattle, including lactating dairy cows. Like all avermectins and milbemycins, eprinomectin acts by binding to parasite glutamate-gated chloride ion channels and disrupts neurotransmission leading to paralysis and death of the parasite, mite or insect.

Eprinomectin is a semisynthetic avermectin that consists of a mixture of two homologues, eprinomectin B1a (4 epi-acetylamino-4 -deoxy-avermectin B1; 90%) and eprinomectin B1b (10%).Eprinomectin was developed as a topical endectocide for all categories of cattle including lactating dairy cattle, and the process by which eprinomectin was selected for further development has been described (90). Briefly, several hundred avermectin/ milbemycin analogues were screened in a sheep model for efficacy against a range of endoparasites and in lactating dairy cows for a low milk:plasma partitioning ratio. Themilk:plasma ratio for eprinomectin is <0.2; ivermectin, by comparison, partitions equally between milk and plasma.

Eprinomectin is an avermectin with anthelmintic and insecticidal activities. It is comprised of eprinomectin B_1a (Item No. 28130) and eprinomectin B_1b (Item No. 27994). Eprinomectin (≥0.08 mg/kg, applied topically) reduces worm burden by 99% or more in bovine models of adult H. placei, O. ostertagi, T. axei, Cooperia punctata, N. helvetianus, O. radiatum, or D. viviparus infection. It also reduces parasite burden in bovine models of horn fly (H. irritans) or mange mite (C. bovis) infestation, as well as in cows naturally infested with lice (L. vituli), when applied topically at doses ranging from 0.16 to 0.5 mg/kg. Formulations containing eprinomectin have been used in the treatment and control of a variety of endo- and ectoparasites in cattle.

Eprinex [Veterinary](Merial).

In cattle, eprinomectin is indicated for a variety gastrointestinal roundworms including adult and L4 stages of Haemonchus placei, Ostertagia ostertagi, Trichostrongylus axei and colubriformis, Cooperia oncophora/punctata/surnabada, Nematodirus helvetianus, Oesophagostomum radiatum, Bunostomum phlebotomum, and Trichuris spp. (adults only); cattle grubs; lice; mange mites; horn flies (for 7 days after treatment), and lungworms (Dictyocaulus vivaparus—for 21 days after treatment).
Topical eprinomectin may be useful for the topical treatment of ear mites (Psoroptes cuniculi) in rabbits. One small study (6 subjects) showed partial response when rabbits were dosed at 5 mg/kg topically, twice at 14 day intervals. (Ulutas, Voyvoda et al. 2005)

Store at -20°C

Acute oral LD₅₀ for rats: 55mg/kg