I am on warfarin for AFib. I also take Metoprolol 25 mg. X2, Sertraline 25 mg, Amlodipine 5 mg. I recently quit Montelukast and Prvastatin, because of side effects I seem to be having that they could contribute to. SE: crawling tingling in left arm chest and back. Tightening of neck with small spasms at times. I stopped warfarin one day, and did not have neck things, but head feels full! I see my cardiologist on the 18th and will address these things with him, but thought I would ask you!