Artemether 5 versus 7 day regimen for severe falciparum malaria.

Twenty-eight male Thai patients with severe falciparum malaria were randomized to receive either artemether for a 5 (300 mg initial dose followed by 100 mg for another 4 days) or a 7 days regimen (160 mg initial dose, followed by 80 mg daily for another 6 days). Thirteen patients received a 5 day regimen and 15 received 7 day regimen. The follow-up period was 28 days. The patients in both groups were comparable in age, body weight, admission parasitemia, hematocrit and white cell count. There were 4 patients in each group who presented with cerebral malaria. The median values of parasite and fever clearance times (PCT and FCT) in the 5 and 7 days regimens were 52 vs 60 hours, and 85 vs 68 hours, respectively. There were 8 and 4 patients, respectively who had recrudescence during days 15 to 25. The cure rates were 38% (95% CI = 14-68%) and 73% (95% CI - 50-96%), respectively for 5 and 7 day regimens. None died in either group. No patients in either group had neurological sequelae after recovery of consciousness. Clinically adverse effects in either group were transient pain at the site of injection. No drug related biochemical or ECG changes were noted in either group. The duration of treatment is the determinant of the cure rate; however, the duration of even 7 days still resulted in high recrudescence rate. It may be necessary to combine artemether with other longer half-life antimalarials to improve the cure rate.

Quinine toxicity when given with doxycycline and mefloquine.

The pharmacokinetic and dynamic interactions among 3 antimalarials, ie quinine, doxycycline and mefloquine was observed in a 26-year-old Thai male patient with falciparum malaria. During the acute episode of the infection, the patient was treated with an intravenous dose of quinine hydrochloride at 600 mg qid, together with an oral dose of doxycycline 100 mg bid. Due to nausea, tinnitus and the persistence of parasitemia in peripheral blood smears, the dose of quinine was reduced 2 days after the first treatment to 300 mg; concurrently oral mefloquine 750 mg was given as 2 divided doses at 24 hours apart. During the course of treatment, the patient developed hearing loss; deafness of the right ear lasted for one week after stopping quinine administration. Higher plasma quinine and lower whole blood mefloquine concentrations than would be expected from the simulation profiles were detected 4 days after the first treatment. However, the concentration of mefloquine was increased upon the cessation of quinine treatment.