STUDY OBJECTIVE: To determine the effect on the international normalized ratio (INR) of adding azithromycin to patients receiving stable dosages of warfarin. DESIGN: Retrospective chart review. SETTING: Outpatient clinic. PATIENTS: Ambulatory patients receiving warfarin and azithromycin concurrently who had a documented therapeutic INR value before the start of azithromycin therapy (pre-INR) and a documented INR value within 30 days after the start of azithromycin therapy (post-INR). MEASUREMENTS AND MAIN RESULTS: Patients given felodipine during long-term warfarin therapy formed a comparative control group. Patient demographics were similar in both treatment groups. Mean age of the azithromycin group (17 patients) was 59 +/- 13 years and of the control group (20 patients) 65 +/- 12 years. All 17 patients in the azithromycin group and 16 of the controls were women. Mean change from pre-INR to post-INR in the azithromycin and control groups, respectively, was 0.14 +/- 0.64 (pre-INR 2.46, post-INR 2.61) and 0.19 +/- 0.54 (pre-INR 2.46, post-INR 2.66) (p = 0.74). A post hoc power analysis based on a pooled standard deviation of 0.60 revealed that the study had 68% power to detect a 0.5 change in the INR value. CONCLUSION: No interaction between azithromycin and warfarin was observed in ambulatory patients with therapeutic baseline INR values.
STUDY OBJECTIVE: To determine the effect on the international normalized ratio (INR) of adding azithromycin to patients receiving stable dosages of warfarin. DESIGN: Retrospective chart review. SETTING:Outpatient clinic. PATIENTS: Ambulatory patients receiving warfarin and azithromycin concurrently who had a documented therapeutic INR value before the start of azithromycin therapy (pre-INR) and a documented INR value within 30 days after the start of azithromycin therapy (post-INR). MEASUREMENTS AND MAIN RESULTS:Patients given felodipine during long-term warfarin therapy formed a comparative control group. Patient demographics were similar in both treatment groups. Mean age of the azithromycin group (17 patients) was 59 +/- 13 years and of the control group (20 patients) 65 +/- 12 years. All 17 patients in the azithromycin group and 16 of the controls were women. Mean change from pre-INR to post-INR in the azithromycin and control groups, respectively, was 0.14 +/- 0.64 (pre-INR 2.46, post-INR 2.61) and 0.19 +/- 0.54 (pre-INR 2.46, post-INR 2.66) (p = 0.74). A post hoc power analysis based on a pooled standard deviation of 0.60 revealed that the study had 68% power to detect a 0.5 change in the INR value. CONCLUSION: No interaction between azithromycin and warfarin was observed in ambulatory patients with therapeutic baseline INR values.
Authors: Jacques Baillargeon; Holly M Holmes; Yu-Li Lin; Mukaila A Raji; Gulshan Sharma; Yong-Fang Kuo Journal: Am J Med Date: 2012-02 Impact factor: 4.965
Authors: Yuanyuan Wang; Muh Akbar Bahar; Anouk M E Jansen; Janwillem W H Kocks; Jan-Willem C Alffenaar; Eelko Hak; Bob Wilffert; Sander D Borgsteede Journal: J Antimicrob Chemother Date: 2019-10-01 Impact factor: 5.790