I take a tablet called tenormin (atenolol).is it safe?

Yes: Properly prescribed and in the right settings and conditions, this is a very safe and effective medication. It has many uses. As with all medications, there are side effects and some will have unusual and "idiosyncratic" reactions to the medication. If you have concerns, speak openly and frankly with your prescribing doctor or discuss with a pharmacist/pharm. D.