Delta 90 SR Tablet is used to treat angina (heart-related chest pain), high blood pressure, and some types of irregular heartbeats (arrhythmia). It is known as a calcium channel blocker. It works by relaxing blood vessels to lower blood pressure. This helps to reduce the workload of the heart. Delta 90 SR Tablet may be taken with or without food, but it is better to take it regularly at a fixed time each day as advised by your doctor. Keep using this medicine even if you feel well. If you stop taking it suddenly, your condition may worsen. This medicine is only part of a treatment program that should include a healthy diet, regular exercise, and weight reduction as advised by your doctor. Common side effects seen with this medicine include headache, constipation, dizziness, fatigue, nausea, flushing, and rash. These are usually mild and disappear after a short time. Consult your doctor if they bother you or do not go away. It may also make you feel sleepy or dizzy, so be careful if you drive or do anything that requires you to be alert. Drinking alcohol should be avoided while taking this medicine as it may worsen the side effects. Before taking this medicine, let your doctor know if you have any liver or kidney problems. Also, inform your doctor if you have very low blood pressure (hypotension), heart failure, or if you recently had a heart attack and have fluid in your lungs. Your doctor may want to monitor your blood pressure while using it and you may need frequent blood tests. Pregnant or breastfeeding women should consult their doctor before taking it.