hi
yes the tablet should be taken along with breakfast or after it ,though it can be taken even after lunch also,basic theory behind this is that you houl not be empty stomach at the time of taking this medicine ,and should repeat the dose exactly after 24 hours
the advantage of taking this medicine along with breakfast i.e 8am is that serum cortisol(hormone increasing bp) is more active during moprning times so bp can shoot up at that time
so its advised that it should be taken in morning with breakfast
atenolol is a betablocker , if we go by books there are a number of side effect
but practically you are on 12 years without any side effect ,its a very safe drug and can be continued life time
however some of the most common side effects encountered are
tiredness,
dizziness,
depression, cold hands and feet, nausea, and slow
heart rate,loss of libido,but generally they are encountered at higher doses
thanks