It's very potent but it does not kill mites eggs but rather the hatchlings when used repeatedly at the appropriate intervals and dosage.
Ivermectin is well absorbed orally, parenterally, and as pour-on formulas. Efficacy is greatest in oral, and in SQ treatment.
Concentration of the drug remains in the body fluids for extended periods with the highest concentration being in the liver and fat tissues. The drug does not easily penetrate cerebral spinal fluid which minimizes toxicity. It is metabolized in the liver, and mostly excreted in feces with a lesser amount excreted in urine.
dosages
Ivermectin 200 mcg/kg to 400 mcg/kg, PO , SQ, repeat in 8-10 days 2. May be applied as a topical behind the ear.
or
Ivermectin 0.2 mg/kg q7 days x 3 weeks; PO, SQ, 1. May be applied as a topical behind the ear.