... having attacks that cause stuttering and uncontrollable shaking on one side (leg and arm). These have continued to occur and have progressed to him almost passing out. He had a stroke in 2015 with no lasting effects. We have taken him to the ER multiple times and he has been admitted for tests but we have not been given a diagnosis or a way to prevent these attacks. He never had any issues until he began Coumadin. Can these issues be a side effect of the medication? He is non-insulin dependent diabetic and has hypothyroidism.