Comparison of ivermectin and diethylcarbamazine in the treatment of onchocerciasis

N Engl J Med. 1985 Jul 18;313(3):133-8. doi: 10.1056/NEJM198507183130301.


We compared ivermectin with diethylcarbamazine for the treatment of onchocerciasis in a double-blind, placebo-controlled trial. Thirty men with moderate to heavy infection and ocular involvement were randomly assigned to receive ivermectin in a single oral dose (200 micrograms per kilogram of body weight), diethylcarbamazine daily for eight days, or placebo. Diethylcarbamazine caused a significantly more severe systemic reaction than ivermectin (P less than 0.001), whereas the reaction to ivermectin did not differ from the reaction to placebo. Diethylcarbamazine markedly increased the number of punctate opacities in the eye (P less than 0.001), as well as the number of dead and living microfilariae in the cornea over the first week of therapy. Ivermectin had no such effect. Both ivermectin and diethylcarbamazine promptly reduced skin microfilaria counts, but only in the ivermectin group did counts remain significantly lower (P less than 0.005) than in the placebo group at the end of six months of observation. Analysis of adult worms isolated from nodules obtained two months after the start of therapy showed no effect of either drug on viability. Ivermectin appears to be a better tolerated, safer, and more effective microfilaricidal agent than diethylcarbamazine for the treatment of onchocerciasis.

Publication types

  • Clinical Trial
  • Comparative Study
  • Controlled Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Anthelmintics / therapeutic use*
  • Antiparasitic Agents
  • Clinical Trials as Topic
  • Cornea / parasitology
  • Corneal Opacity / chemically induced
  • Diethylcarbamazine / adverse effects
  • Diethylcarbamazine / therapeutic use*
  • Double-Blind Method
  • Eye Diseases / drug therapy
  • Eye Diseases / etiology
  • Filaricides / adverse effects
  • Filaricides / therapeutic use*
  • Humans
  • Ivermectin
  • Lactones / adverse effects
  • Lactones / therapeutic use*
  • Male
  • Middle Aged
  • Onchocerciasis / complications
  • Onchocerciasis / drug therapy*
  • Onchocerciasis / parasitology
  • Random Allocation
  • Skin / parasitology
  • Skin Diseases, Parasitic / parasitology
  • Time Factors


  • Anthelmintics
  • Antiparasitic Agents
  • Filaricides
  • Lactones
  • Ivermectin
  • Diethylcarbamazine