Vermectin Mechanism of Action

Pharmacology: Pharmacodynamics: Ivermectin is a semisynthetic anthelminthic agent; it binds selectively and with strong affinity to glutamate-gated chloride ion channels which occur in invertebrate nerve and muscle cells. This leads to increased permeability of cell membranes to chloride ions then hyperpolarization of the nerve or muscle cell, and death of the parasite.
Pharmacokinetics: Tablet: Absorption: Well absorbed.
Distribution: V_d: 3.1 to 3.5 L/kg (healthy males); high concentration in the liver and adipose tissue; does not readily cross the blood-brain barrier.
Protein binding: ~93% primarily to albumin.
Metabolism: Hepatic via CYP3A4 (major), CYP2D6 (minor), and CYP2E1 (minor).
Half-life elimination: 18 hours.
Time to peak, serum: ~4 hours.
Excretion: Feces; urine (<1%).
Half-life elimination: 18 hours.
Time to peak, serum: ~4 hours.
Solution for injection: There are no pharmacokinetic data on subcutaneous ivermectin in humans but the kinetics have been studied extensively in large animals. The time to maximum concentration (Cmax) in large animals ranges from 1.2 to 4 days. Assuming an absorption half-life in humans of approximately one day (extrapolated from animal data) and a relatively short elimination half-life of 12-56 hours, steady state should be reached within one week of multiple dosing. Subcutaneous administration produced significantly higher ivermectin levels (11.4-17.2 ng/mL) than oral administration in patients with disseminated strongyloidiasis.
Distribution: V_d: 3.1 to 3.5 L/kg (healthy males); high concentration in the liver and adipose tissue; does not readily cross the blood-brain barrier.
Protein binding: ~93% primarily to albumin.
Metabolism: Hepatic via CYP3A4 (major), CYP2D6 (minor), and CYP2E1 (minor).
Excretion: Feces; urine (<1%).