The side effects for me from metroprolol 25 mg tablet each day in divided dose of 1/2 tables in AM and the other 1/2 in the PM. Were : dizziness/ lightheadedness, tiredness,depression,dry mouth, itching, cold feet, runny nose, sudden shortness of breath, rapid-pounding heartbeat.....at night about an hour after taking the evening dose, I would wake up feeling the pounding heartbeat, shortness of breath ...almost like waking up from a bad nightmare. I talked to a PA at my cardiology docs office and was advised to decrease the dose, skip doses, stop taking the pill altogether or whatever made me feel better.....this was amazing as I thought my life depended on taking this drug. I stopped the AM dose and within two days, most of the symptoms disappeared. The remaining Sx occurred after I was already asleep....the pounding heartbeat, nightmares and SOB....this occurred about an hour after taking the PM dose...I had been off the AM dose about 4 weeks and decided to omit the PM dose. I have been off the PM dose for a week and have had no more episodes at night. My purpose in this long account is to say that side effects can be a real problem of any drug. I was put on the drug on 2/14/19....and it took a while for me to realize that the drug was causing mega problems.