Objective: To determine the prevalence and profile of adverse drug reactions (ADRs) of voriconazole in Thai patients.

Material and Method: A retrospective, descriptive study was conducted in in-patients who received voriconazole at Ramathibodi Hospital during the period of 1st July 2005 to 31st March 2008. Patients’ profiles were reviewed for adverse drug events (ADEs) of voriconazole. The causality assessment of ADRs was performed by a clinical pharmacist and a physician using Naranjo’s algorithm. ADR data were classified based on system-organ classification arranged by WHO Collaborating Centre for International Drug Monitoring. Prevalence, onset, duration and severity as well as outcome of ADRs were determined.

Results: One hundred and twenty-eight patients’ profiles (62 males, 66 females) were assessed with 162 voriconazole use episodes. In total, 94 patients had ADRs from 114 voriconazole use episodes. The prevalence of ADR was therefore 70.4%. ADRs were mostly expressed as liver and biliary system disorders (54.6%). These included the pattern of cholestatohepatitis, cholestatic jaundice, increased liver function tests (LFTs), transaminitis and hyperbilirubinemia. The second most common ADRs were metabolic and nutritional disorders (17.3%). Disorders in central and peripheral nervous systems were observed in 2.2% while visual disturbances and skin rash were less common.

Conclusion: High prevalence of ADRs of voriconazole was revealed. Liver and biliary system disorders were the most frequent ADRs found. Even though most ADRs could be recovered and were not life-threatening, careful detection and monitoring of ADRs are still required for voriconazole-treated patients.