Continiously hiccups. To stop hiccups?

Hi sir, My father gone through heart bypass surgery on 31st Decand discharged from hospital on 14th jan, surgery got infection after 2days and admitted again admitted in hospital we have been almost 20days to recover from infection, he is diabetic everyday we give 2times insulin 28 morning 32 night , he is recovering from surgery but since 1week he is suffering with continuous hicckups, we took him to same doctor where surgery done, he told no need to worry reason told for hiccups is low sugar level bit when we asked diabetic doctor he told low sugar levels is not a reason for hiccups, doctor suggested us tablet Pan-D , now we are using tablet but hiccups dint stop, please suggest us to stop hiccups thanks