This is an experimental placebo controlled double blinded study. Study group is 30 identified patients who are randomly allocated in drug or placebo group. All of the patients are advised stop smoking and receive standard routine therapy of Buerger`s disease. Inclusion criteria contains: Buerger`s patients referring to Alzahra hospital who have consent of participation to study. No history of hypertension, diabetes mellitus, ischemic heart disease, cerebrovascular disease or collagen vascular disease. Exclusion criteria are: surgical (sympathectomy or vascular bypass) or medical (Illeoprost or corticosteroid) changes in treatment, or starting Aspirin, calcium channel blocker, VitB6 or VitB12 or stop smoking during the study. At the start of the study demographic data, Wagner wound scale, Visual Analog Scale (VAS) of pain, Allen test, healing scale, wound size and major and minor amputation, homocysteine, anticardiolipin and number of steps walking without pain is recorded. Intervention is was one tablet containing 5 mg Folic acid and placebo (the same as color, size, and weight). The patients will be evaluate at the first , 2nd and 6th month for Homocysteine, Anticardiolipin, scale of wound, scale of pain, size of wound, major and minor amputation, sense of patient about healing and the number of steps the patient can walk without pain.