CO-DIOVAN 80/12.5MG SACHET is a combination of two medicines: Valsartan and hydrochlorothiazide which lower blood pressure effectively. It is used to treat high blood pressure which is not adequately controlled by a single substance alone. High blood pressure increases the workload of the heart and arteries.Common side effect may includes headache, fast heartbeat,diziness,heartburn, abdominal/stomach pain. It is important to take this medicine exactly as prescribed by your doctor.