My Wife Has Bronchitis : Prescribed Methylprednisolone & Levofloxacin. She

my wife has bronchitis : prescribed methylprednisolone & levofloxacin. She cant sleep because of the coughing. what over the counter sleep aid would be ok to take with the other medicine? the lack of sleep has made her anxiety go off the charts. she cant shut off her mind and rest....wht can i do?