Thanks for writing in to Healthcare Magic!
Your problem seems to be unrelated to your BP medicines, rather it may be a manifestation of a low cardiac function. If your lone kidney
is functioning sub-optimally then you may be having problem due to fluid overload.
Another possibility may be that you are having some respiratory problem like asthma
or hyper-reactive airways etc which may need separate management.
I would like you to be physically examined and evaluated by a senior physician to get an exact status of your problem.
If you have any further query please let me know I would try to answer it for you.
Wish you a great health!