Comparing efficacy and safety of high-dose and standard-dose rifampicin in the treatment of brucellosis: a randomized clinical trial

Abstract Background In a few studies, higher doses of rifampicin improved the outcome of patients with TB. There is no information regarding efficacy and safety of higher doses of rifampicin in patients with brucellosis. Objectives To compare efficacy and safety of higher and standard doses of rifampicin, each with doxycycline, in the treatment of patients with brucellosis. Methods Within a randomized clinical trial, clinical response and adverse events of high-dose rifampicin (900–1200 mg/day) plus doxycycline 100 mg twice daily were compared with standard-dose rifampicin (600 mg/day) plus doxycycline 100 mg twice daily in 120 patients with brucellosis. Results Clinical response occurred in 57 (95%) of patients in the high-dose group and 49 (81.66%) of patients in the standard-dose group (P = 0.04). The most common adverse events of the treatment were nausea (37.5%), skin rash (13.33%), vomiting (10%) and transaminitis (7.22%). Incidence of these events was comparable between the groups. Conclusions The rate of clinical response in patients with brucellosis who were treated with high-dose rifampicin plus standard-dose doxycycline was significantly higher than in the patients who received the standard doses of rifampicin and doxycycline, without further adverse events. The high-dose rifampicin therefore improved clinical response in patients with brucellosis with a similar safety profile to the standard dose. If these findings are confirmed in future studies, higher doses of rifampicin may be recommended for treatment of patients with brucellosis.