Mefloquine is a quinoline compound closely related to quinine and is characterized by its long half-life and excellent clinical efficacy against chloroquine-resistant falciparum malaria. Even recently, the cure rate for falciparum malaria after its use is over 90% in many parts of the world such as most of African countries. However, it is reported to be less effective in Thai-Cambodian or Thai-Burmese border. The higher dose of mefloquine, e.g. 25mg/kg, is required in these areas, but even so unsatisfactory results often ensue. In these areas, mefloquine is used combined with other antimalarials such as qinghaosu derivatives or tetracyclines showing better results. Reported adverse reactions after the therapeutic use of mefloquine include dizziness, nausea, vomiting, diarrhea, headache and so on. With regards to dizziness, however, various figures of its occurrence are reported, probably due to its subjective nature. In addition to the above symptoms, we have to be extemely cautious about the severe neuropsychiatric reactions caused by mefloquine that are reported to occur in one out of 215 cases.
We analyzed the data on 27-28 patients with falciparum malaria who were treated in our hospital with 750-1, 500mg of mefloquine. All but one case were successfully treated without later recrudescence. About one third of the cases experienced undesirable symptoms attributable to the medication, however, most of them were slight and did not require medical intervention. It is likely that mefloquine could be a first-choice drug for uncomplicated falciparum malaria in Japanese as well as in other people.
