Description: Telmisartan is a type of ARB drug that helps lower high blood pressure. In addition to being a major risk factor for heart disease, hypertension also increases the risk of stroke, kidney failure, congestive heart failure, and dementia. Hydrochlorothiazide is a diuretic that reduces the amount of water in the body. When taken orally, hydrochlorothiazide reduces extracellular fluid volume by increasing its excretion via urine. It also causes the kidneys to conserve sodium and potassium ions.