Topical ivermectin in the treatment of pediculosis capitis

Background: Head lice infestation is considered a prominent issue because of its worldwide distribution, especially among children. Millions of children are infested with pediculosis capitis every year. The increasing rate of lice infestation has been reported even in the developed countries due to the resistance to known pediculicides. Besides, the louse is a vector for serious diseases, such as epidemic typhus fever. Objective: The aim of this work was the search for a new cheap and effective drug for pediculosis capitis. 2% ivermectin solution, a promising novel drug used for endoparasite and ectoparasite infections, was used in this study. Materials and Methods: This was a clinical trial study. The in vitro study was carried out in a period of five months. Samples of nits and lice were collected from female patients of the Department of Dermatology and Venereology, Baghdad Teaching Hospital. The study was conducted during a period from October 2002 through November 2003. One hundred fifty children from four primary schools in Hayy Al-A’amel, Baghdad, participated in this part of the study. The preparation was applied to the children by the author. One hundred children were tested with ivermectin solution and fifty children with rectified spirit. The first part of the study involved a parasitological evaluation (in vitro study) of pediculicidal and ovicidal activity, in which 4% ivermectin solution was discontinued because of contact dermatitis. Therefore, 2% ivermectin solution was used instead. Pediculicidal and ovicidal activity was examined half an hour afterward. The second part of the study involved a clinical evaluation (in situ study) of 2% ivermectin solution for half an hour. Results: Topical 2% ivermectin solution in rectified spirit is a good pediculicidal (100%) and a good ovicidal (88%) drug with good therapeutic efficacy (82% after the first application, 90% after the second application) against pediculosis capitis. Conclusion: The study described a novel topical preparation for pediculosis capitis, which was proven effective and safe.