Causes increased permeability, influx of chloride ions, hyperpolarization, and muscle paralysis; affects the microfilariae, but does not kill the adult worm.
Assess for signs and symptoms of Mazzotti reaction of skin (pruritus, rash, urticaria), eyes (conjunctivitis, eye pain, eye pruritus, eyelid swelling, blurred vision, photophobia, changes in visual acuity, hyperemia, ocular discomfort, watery eyes), and systemic reactions (headache, fever, hypotension, tachycardia, edema, lymphadenopathy, arthralgia, myalgia, chills, paresthesia, asthenia). Usually occur and resolve during 1st wk after dose of moxidectin. Treat symptomatically with oral hydration, recumbency, antihistamines and/or analgesics. May use IV 0.9% NaCl, and/or parenteral corticosteroids to treat orthostatic hypotension.
Assess for symptomatic orthostatic hypotension (inability to stand without support after lying down for 5 minutes) following dose. Usually transient occurring Days 1 and 2 after dose. Manage by having patient lie down until symptoms resolve.
Assess for edema and worsening onchodermatitis (pruritus, unilateral leg or forearm swelling, rash, eye symptoms) after therapy. Treat symptomatically.
Lab Test Considerations:
Monitor for Mazzotti reactions after therapy. May cause eosinophilia, eosinopenia, lymphocytopenia, neutropenia, and ↑ALT, AST, gamma glutamyl transferase (GGT) and LDH. May also cause proteinuria.