Olbet-Trio 20 Tablet is a combination of medicines used to treat hypertension (high blood pressure) when a single medication is not effective. It helps to lower high blood pressure thus reduces chances of future heart attack and stroke. Olbet-Trio 20 Tablet should be taken with or without food. The dose will depend on your condition and how you respond to the medicine. Try to take it at the same time each day. It is important to keep taking this medicine until your doctor tells you not to. It contains a diuretic (water pill) and will make you urinate more so, it is best to avoid taking this medicine within four hours of going to bed. Use this medicine regularly to get the most benefit from it even if you feel well. High blood pressure does not usually have symptoms and if you stop taking it your risk of heart attack or stroke may increase. The most common side effects of this medicine include ankle swelling, headache, dizziness, tiredness, and taste change. Consult your doctor If any of these bother you, or get worse, or won't go away. Drink plenty of fluids while taking medicine to overcome muscle weakness, dry mouth, and extreme thirst. Before taking it, let your doctor know if you have any liver or kidney problems. Pregnant or breastfeeding women should also consult their doctor for advice before taking this medicine. You also need to tell your doctor what other medicines you are taking especially those used to treat high blood pressure or heart conditions. You should have your blood pressure, kidney function, level of electrolytes, and blood sugar level checked regularly to make sure that this medicine is working properly.