OBJECTIVES: The objective of this study was to assess how often St. John's wort (SJW) is prescribed with medications that may interact dangerously with it. DESIGN: The study design was a retrospective analysis of nationally representative data from the National Ambulatory Medical Care Survey. SETTINGS: The study setting was U.S. nonfederal outpatient physician offices. SUBJECTS: Those prescribed SJW between 1993 and 2010 were the subjects. OUTCOME MEASURES: The outcome measures were medications co-prescribed with SJW. RESULTS: Twenty-eight percent (28%) of SJW visits involved a drug that has potentially dangerous interaction with SJW. These included selective serotonin reuptake inhibitors, benzodiazepines, warfarin, statins, verapamil, digoxin, and oral contraceptives. CONCLUSIONS: SJW is frequently used in potentially dangerous combinations. Physicians should be aware of these common interactions and warn patients appropriately.
OBJECTIVES: The objective of this study was to assess how often St. John's wort (SJW) is prescribed with medications that may interact dangerously with it. DESIGN: The study design was a retrospective analysis of nationally representative data from the National Ambulatory Medical Care Survey. SETTINGS: The study setting was U.S. nonfederal outpatient physician offices. SUBJECTS: Those prescribed SJW between 1993 and 2010 were the subjects. OUTCOME MEASURES: The outcome measures were medications co-prescribed with SJW. RESULTS: Twenty-eight percent (28%) of SJW visits involved a drug that has potentially dangerous interaction with SJW. These included selective serotonin reuptake inhibitors, benzodiazepines, warfarin, statins, verapamil, digoxin, and oral contraceptives. CONCLUSIONS: SJW is frequently used in potentially dangerous combinations. Physicians should be aware of these common interactions and warn patients appropriately.