Hi, Horse chestnut but contains escin which is thought to improve blood circulation, an important entity of treating varicose veins. However most of the research is inconclusive though there is some evidence it probably reduces lower leg volume, circumference at calf and ankles. Its side effects are dizziness, nausea, headache and itching although rare. I personally to advise to use it in mild cases of varicose veins as the side effects are low and some evidence is there of its efficacy. However, if the varicose veins are large enough, then in these severe cases I would advise you to consult a doctor. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Muhammad Zahir Shah, Internal Medicine Specialist