Final answer:
Renal impairment is a concern for patients receiving dabigatran (Pradaxa) for atrial fibrillation because it can lead to drug accumulation and an increased risk of bleeding.
Step-by-step explanation:
If a patient is receiving dabigatran (Pradaxa), a direct thrombin inhibitor, for the treatment of atrial fibrillation, the condition of concern when prescribing this medication at a dose of 150 mg twice daily would be renal impairment. Dabigatran is primarily excreted by the kidneys, and in patients with renal impairment, the risk of bleeding increases due to accumulation of the drug. It is important to monitor renal function in patients taking dabigatran and adjust the dose accordingly or consider alternative therapies if necessary.