Antogin ER 500 mg Tablet contains Ranolazine, a medication used to treat chronic angina (chest pain). Unlike traditional anti-anginal drugs, Ranolazine works by inhibiting late sodium currents in heart cells, which helps to relax the heart muscle and improve blood flow without significantly affecting heart rate or blood pressure. This makes it suitable for patients who do not respond adequately to other anti-anginal therapies. The "ER" in the name stands for "Extended Release," indicating that the tablet releases the medication slowly over time, allowing for twice-daily dosing. It's important to take the tablet whole, without crushing or chewing, and it can be taken with or without food.