Amoxicillin-clavulanic acid therapy may be associated with severe side effects -- review of the literature.

INTRODUCTION: There is a growing body of evidence that amoxicillin-clavulanic acid may induce severe adverse effects in patients.

METHODS: A medline search of case reports and reviews on amoxicillin-clavulanic acid induced adverse effects was performed. The criteria of a consensus conference on the reporting of drug-induced liver disease were applied.

RESULTS: Amoxicillin-clavulanic acid has been associated with drug-induced cholestatic hepatitis in 208 reported patients. In 153 evaluable patients there were 106 males and 47 females with a mean age of 60 years (1-90). Liver associated co-morbidity and co-medication does not play a major part in the development of disease. In most instances respiratory tract infection and sinusitis were treated by amoxicillin-clavulanic acid with a mean treatment duration of 13.9 days and a reaction time until first onset of jaundice of 25.2 days average. Infection and cholestasis from other reason were ruled out in most patients. Liver injury was classified according to laboratory parameters to be hepatocellular in 35 patients, cholestatic in 24 patients and mixed in 83 patients. Normalization of liver enzymes was observed 11.5 weeks after onset of drug administration (average); three of 153 patients did not survive the adverse event.

CONCLUSION: Amoxicillin-clavulanic acid which is marketed for treatment of respiratory infections and sinusitis/otitis may in some cases induce severe adverse effects and death in patients of different age, especially if they are on multidrug regimens. In consideration of this fact many authors recommend to reflect carefully, whether amoxicillin-clavulanic acid is necessary in treatment of patients with localized or uncomplicated infections. If amoxicillin-clavulanic acid is prescribed, transaminase, alkaline phosphatase and bilirubin tests should be obtained within the first two weeks and after four to five weeks after beginning of treatment to recognize early enough undesired hepatic side effects.