ISTIN is a brand name for a medication that contains the active ingredient amlodipine, which belongs to a class of drugs known as calcium channel blockers. It is primarily used to treat high blood pressure (hypertension) and to prevent certain types of chest pain (angina). By relaxing the blood vessels, ISTIN helps to improve blood flow and reduce the workload on the heart, thereby lowering blood pressure and increasing the supply of blood and oxygen to the heart. This medication is commonly prescribed due to its effectiveness and is usually taken once daily, with or without food. Like all medications, ISTIN may have side effects, and it is important to follow the prescribing doctor's instructions and to report any adverse reactions.