WHO DRUG INFORMATION - World Health Organization

18. Black-Payne, C, Bocchini, J., Cedotal, C. Failure oferythromycin ointment for postnatal ocular prophylaxis ofchlamydial conjunctivitis. Pediatric Infectious DiseasesJournal, 8: 491-495 (1989).19. Hedberg, K., Ristinen, T., Soler, J. et al. Outbreak oferythromycin-resistant staphylococcal conjunctivitis in anewborn nursery. Pediatric Infectious Diseases Journal, 9:268-273(1990).20. Laga, M., Plummer, F., Piot, P. et al. Prophylaxis ofgonococcal and chlamydial ophthalmia neonatorum: acomparison of silver nitrate and tetracycline. New EnglandJournal of Medicine, 318: 653-657 (1988).21. Houang, E., Gilmore, O., Reid, C, Shaw, E. Absenceof bacterial resistance to povidone iodine. Journal ofClinical Pathology, 29: 752-755 (1976).22. Benevento, W., Murray, P., Reed, C, Pepose, J. Thesensitivity of Neisseria gonorrhoeae, Chlamydia trachomatis,and herpes simplex type II to disinfection withpovidone-iodine. American Journal of Ophthalmology,109:329-333(1990).23. Nahmius, A., Visintine, A., Caldwell, D., Wilson, L. Eyeinfections with herpes simplex viruses in neonates. Surveyof Ophthalmology, 21: 100-105 (1976).24. Apt, L., Isenberg, S., Yoshimori, R., Paez, J. Chemicalpreparation of the eye in ophthalmic surgery. III. Effect ofpovidone iodine on the conjunctiva. Archives of Ophthalmology,102: 728-729 (1984).25. Speaker, M., Menikoff, J. Prophylaxis of endophthalmitiswith topical povidone-iodine. Ophthalmology, 98:1769-1775(1991).26. Isenberg, S., Apt, L, Yoshimori, R. et al. Povidoneiodinefor ophthalmia neonatorum prophylaxis. AmericanJournal of Ophthalmology, 118: 701-706 (1994).27. Isenberg, S., Apt, P., Wood, M. A controlled trial ofpovidone-iodine as prophylaxis against ophthalmia neonatorum.New England Journal of Medicine, 332: 562-566(1995).Ivermectin: an effective acaricideAs a result of generous and free supplies by theMerck pharmaceutical company through theMectizan Donation Programme, ivermectin hasbecome indivisibly associated with the control ofonchocerciasis. However, its value is now alsoestablished in lymphatic filariasis (see page 132)and interest is emerging in its broader antiparasiticproperties.Ivermectin is a chemically-modified form of amember of a class of macrocyclic compoundscalled avermectins that are apparently unique to astrain of actinomycetes called Streptomycesavermitilis which was isolated during large-scalescreening of samples of Japanese soil in the 1970s(1). Although it is structurally similar to the macrocycliclactone antibiotics, ivermectin has no antibacterialactivity. It is exceptional, however, in that itis highly active against a wide range of parasitesthat infect animals and man, including nematodeworms, mites (acarines), and insects (2).Among the uses for which ivermectin is alreadyestablished in veterinary medicine is the treatmentof sarcoptic mange, a mite infection in domesticatedanimals. Early attempts to use it in the treatmentof human scabies — which is also caused bya variety of the same organism, Sarcoptes scabiei— provided inconsistent and sometimes disappointingresults. In the Pacific islands a single oral doseof ivermectin (100 μg/kg) cured 70% of the treatedpatients — a substantially higher proportion thanwere cured by a standard course of benzyl ben¬zoate applications (3). Similar results were reportedfrom a trial conducted in Mexico in which patientswere treated with ivermectin, 200 μg/kg (4). InIndia, however, a dose of 100 μg/kg has beenreported to be inadequate (5), while in West Africaa single oral dose of either 100 or 200 μg/kg wasconsidered to be no more effective than placebo(6).In the light of these findings, the results of a recentopen uncontrolled study — which involvedotherwise healthy individuals and immunodeficientpatients with HIV infection — are reassuring (7).Scabies was parasitologically confirmed in all 22patients admitted to the study and each received asingle oral dose of ivermectin, 200 mcg/kg. After 4weeks, no sign of scabies was detected in any of11 otherwise healthy patients. Scabies was alsoapparently eradicated in all but one of 11 patientswith HIV infection (although two of these patientsreceived a second dose of ivermectin 2 weeks afterthe first). The remaining patient, who was seriouslyill with advanced AIDS and tuberculosis, waseventually cured of extensive, heavily crustedscabies after a third dose of ivermectin and totalbody treatment with 5% permethrin cream appliedunder supervision.The authors conclude that a single oral dose ofivermectin will cure most cases of scabies, but thatcrusted or other stubborn cases may requireadditional treatment. They stress the need,however, for community treatment since, within two