Numbness,heatbeat increasing,sweting

Patient: Dear sir,This is for my father. He is 57 years old.he have sugar,BP from 35 age and now he having tablets for that. from last one month he has some problems that he feels numbness in the whole body, at that time his heart beat increses,sweating also happened and he becomes nervous.In a day it will come on one or two times and after sometimes it will comes to normal.he do all the checks, heart,lungs,thyroid etc and doctor telling all are normal and this is becuase of tension. but he telling he has not that much tension. we consulted 3 doctors and they tell that there is nothing to worry.but day by day he is not eating much food and always feels sleepy. please advice me sir.Kind regards,Sharon S