Acute Ischemic Stroke in a Patient with Multiple Sclerosis after Initiating Teriflunomide Treatment: A Challenging Case

Multiple sclerosis is an autoimmune disease of the central nervous system, during which vascular events, including atherosclerosis, are more common and progress faster. Teriflunomide (TFN) is an oral drug that studies have indicated has low side effects alongside high efficiency. In this article, a middle-aged woman with multiple sclerosis was introduced, whose medication was changed to TFN. Thirty-five days later, she presented with focal neurologic symptoms, and investigations reported a lacunar infarction. Having excluded potential causes of acute ischemic stroke, such as vascular and rheumatologic factors, the only identifiable factor was the introduction of a new medication. The process of conclusively attributing TFN as the causative agent requires further clarification in future studies.