My Husband Who Is 82 Suffers From High Blood Pressure

My husband who is 82 suffers from high blood pressure (usually kept under control with drugs) but recently his blood pressure has been quite high along with a fast heart beat, but what he is experiencing is exhaustion, he wakes up tired, he only has to walk to the bottom of the garden which is approx 100 yards and he is exhausted, he saw our GP last week who doubled up his lisinopril to 20mg, this has brought his blood pressure back to what it was but this has not lowered his heart beat nor had any effect on the exhaustion. Our GP has arranged a series of blood tests for later this week. Would it help if I bought him a tonic from the chemist?
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