The Effect of Ibuprofen on Serum Digoxin Concentrations

This study was undertaken to determine the effects of ibuprofen (Motrin), in daily doses of at least 1600 mg, on steady-state digoxin concentrations. A total of 12 ambulatory patients (10, female; 2, male), with a mean age of 66 years (38–81 yr), completed the study. An initial baseline serum digoxin level was obtained, with follow-up levels at 7 days and, whenever possible, 28 days after ibuprofen initiation. Serum creatinine concentrations were not significantly different from baseline to 7 or 28 days of ibuprofen therapy. Results show a statistically significant (p < 0.05) increase in digoxin levels after seven days of ibuprofen. The mean increase was 59 percent (range, 10.7–325.4 percent), with 10 of the 12 patients displaying increased seven-day levels. Digoxin levels drawn 28 days after ibuprofen initiation were not statistically different from baseline or seven-day digoxin levels.