How Can Elevated Blood Pressure Levels Be Treated?

My 97-year old father has slightly elevated blood pressure (around 150-160) and, as he recently found out, two leaky heart valves. His primary care doctor prescribed Dogoxin (125 mg) for high blood pressure, which he takes every other day. A heart doctor he saw prescribed Valsartan for the leaky valves. At first he took half a pill each day. When he experienced no side effects, he was told to up the dosage to one full pill per day. Now he is experiencing nausea when he takes the full 40 mg Valsartan, so he stopped taking it. My questions: should he go back to I/2 pill? Is there a problem with taking Digoxin and Valsartan together? Is there a better medication for his heart issues to try that won t upset his stomach? He doesn t have an appointment with the heart doctor until May 5 and I need to know what he should do for the rest of this week.