Adjust Pradaxa dose for renal impairment
From the February 2011 issue
Healthcare practitioners must pay as much attention to safe prescribing of the oral direct thrombin inhibitor PRADAXA (dabigatran etexilate mesylate) as they would warfarin. In a recent report, Pradaxa was prescribed by a cardiologist for a patient with Stage IV chronic kidney disease. The dose of the medication was not adjusted for the patient’s renal impairment. Instead of the recommended dose of 75 mg BID, the patient received 150 mg BID. Upon a follow-up visit with the cardiologist, the patient complained of weakness, black tarry stools, and was found to have a low hemoglobin and hematocrit. The physician immediately sent the patient to a local emergency department. The patient was admitted to the intensive care unit where he received multiple units of fresh frozen plasma and packed red blood cells for a massive gastrointestinal bleed. Eventually his hemoglobin and hematocrit returned to safe levels, allowing his transfer to a progressive care unit. Among the precautions for Pradaxa is a recommended dose of 75 mg BID for patients with a creatinine clearance (CrCL) of 15-30 mL/min. Dosing recommendations for patients with a CrCL less than 15 mL/min or on dialysis are not provided on the label. Community pharmacists are at a disadvantage to catch these errors as the sharing and transmission of laboratory data from physician offices to community pharmacies is limited. Pharmacists must rely on speaking with the patient and reviewing the patient’s profile to uncover information about the patient’s renal function and intercept possible prescribing errors as described above. If there is uncertainty as to the patient’s renal function, the pharmacist should contact the prescriber. Electronic prescribing systems should have this dosing adjustment appear as an alert for patients with renal impairment.