Ivermectin (22,23-dihydroavermectin B1a + 22,23-dihydroavermectin B1b) is a broad-spectrum antiparasitic avermectin medicine. Ivermectin is positive allosteric modulator of the α7 neuronal nicotinic acetylcholine receptor and the purinergic P2X4 receptor. Antihelmintic. Ivermectin also modulates glutamate- and GABA-activated chloride channels. Ivermectin potentiates glycine-gated currents at low concentrations (30 nM).