Zanidip is a calcium channel blocker. Its hard to get BP meds that dont mess you up in some way. Aldactone is very successful but has lots of sides. Have you had bloods etc to check for secondary causes of BP? Worth a look for sure.
I found quite an improvement in my BP (unmedicated, tested as 90/60) with the last 20 lbs I dropped (getting me to the Lower End of the healthy BMI range). This was a notable improvement from my usual 115/75 or so (just at the threshold of a healthy BP, revised in many areas from a longstanding use of 120/80). And, my blood lipids tested as much improved. I also had a treadmill stress test before and after my modest weight loss, changing my result from 10% under performing for my age, to 10% over performing for my age. I attribute the difference to my heart having less weight to lug around, and, less fatty tissue to pump blood through.
So, I do think any excess weight is a notable concern for heart health and blood pressure. In the absence of major effort, we steadily lose muscle as we age, which means BMI understates how out of shape we are as we age. eg. 180 lbs might be a fine weight for a fit 30 year old, but a flabby weight for a fit 70 year old.
Hi...I'm in the U.S. so I do not recognize the names of any of the drug you posted.
I will say this, though...it is very common to have to be on 2,3 even 4 meds to control BP. It really is an art of tweaking them, trying different combinations, and dosages, until you find the right mix that works for you.
We aren't doctors, but I think you should be working with yours continually until you find what works. Don't give up...there are so many meds for BP...I'm sure that you'll find something that works.
Have you given up all salt? You could try to lose some weight (it might make a bit of a difference) and exercise, as long as your doctor thinks it is safe.
You could also supplement your meds with yoga & meditation. It isn't easy at first...in fact, it is hard for a long time, but then it clicks and you wonder how you ever went without doing that stuff.
Good luck my friend...