Moxidectin is a semi-synthetic milbemycin derived from nemadectin by selective oxidation followed by methyloximation. Moxidectin was patented in 1991 as an anthelmintic for internal parasite control. The presence of the methyloxime affords moxidectin a greater hydrophobicity and longer biological half-life compared to nemadectin. Moxidectin binds selectively to parasite glutamate-gated chloride ion channels and disrupts neurotransmission leading to paralysis and death of the parasite.