Hi. Certain Blood pressure medicines reduce pulse rate, like beta blockers. Which medicine is he on? Also is the pulse rate low even when he walks or does some activity? As in if he walks around or does some physical work does the pulse rate increase proportionately? In a normal person it should. The cause for fatigue and tiredness may be this very low pulse rate or inability of the pulse rate to increase in proportion to activity. In that case he needs to be evaluated
Next Steps
He needs review of medications to see if any of his medication is causing this along with ECG, Holter and other tests to rule out heart rhythm issues if required
Health Tips
Seek consultation for detailed history and evaluation