High blood pressure over an extended period can lead to potentially dangerous complications. This can cause damage to organs, leading to microalbuminuria, cognitive dysfunction, and left-ventricular hypertrophy, as noted by one study. Additionally, the risk of renal failure, dementia and suffering a heart attack also dramatically increases in the population with elevated blood pressure levels.
There are many good options when it comes to such medication. Examples are ACE (angiotensin-converting-enzyme) inhibitors or AII-blockers (angiotensin II receptor blockers) such as Enalapril or Losartan. If this kind of medication doesn’t give the desired effect, you might have to add other medication such as so-called calcium antagonists (e.g. Felodipin) or a mild diuretic (can be found as a combined pill with Enalapril and Losartan).