a uri is typically caused by a virus. and a virus lasts about 7 days and does not respond to any antibitoic so i don't know exactly why your medical provider felt you needed it. school attendance is more dependent on how you feel and the stage of your illness (colds are more contagious the first two days) so you won't know if you can go to school until you really wake up and see how you feel.
i have a uri and i took my first dose of my prescribed z-pak today around 3:30 will i be able to go to school tomorrow?