Atenolol
"I've been on 25 mgs. of Atenolol for 10 years.  Have heard in recent years, that after such time  They are finding IF you're over 60, you should consider switching to another BB.  That supposedly it (atenolol) loses it's effectiveness.  Well when you start researching ALL the beta blockers currently on the market?  You will find that most of them have side effects far more than Atenolol, and while I haven't had any real symptoms, I'm guessing I should "stay put" with Atenolol unless it fails to do the job in the future."