It's an "ACE II (two) Inhibitor," a class of drugs commonly used to treat high blood pressure.
It seems to be tolerated well by most patients, and the evidence for its use is good- (it stops death and illness.)
Its a bit of an unusual choice for first line treatment, usually "ACE inhibitors" would be tried first, changing to "ACE II's" if not tolerated- having said that, it's a reasonable choice.
It's one of a whole host of tablets used to control high blood pressure- there isn't much evidence to say one is more superior than any others, although it's likely you'll have less side effects from this one than others.
Don't be suprised if the doc keeps increasing the dose until optimal bp is reached. And let him know if you feel any different.
More of a general overview here
http://www.pprune.org/medical-health...on-thread.html
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