Hello,
I can understand your concern very well, as you are in new place which is not familial with you.
I want to know few things from your side like your age, if you are having
diabetes or not, taking any other tablets or not, what kind of renal problems you are diagnosed.
I would like to tell you that if you cut down the drug after taking it for past 15 years, then its obvious that your BP will shoot up, because your body is used to these drugs and it requires some time to adapt again with new drug and dose. I personally feel that
atenolol alone will not control your BP and if i were your treating physician, i would advise you few tests like
lipid profile,
serum creatinine, blood sugar, ECG and TMT, if required.
You can come back to me directly anytime after having all the information i have asked, so i can guide you in right direction for betterment of your health.
Kind regards.