My Son (24 Years Old) Has Been Sick With An

My son (24 years old) has been sick with an illness that the Urgent Care said was viral (*they did a flu test and determined it was not the flu). He has been sick for 5 days with a temperature between normal and 102 degrees. We have been alternating Tylenol and Motrin with alcohol rubs to bring the temperature down which has worked but not for a significant time. The Nurse Practitioner suggested Musinex DM. He has an unproductive cough. Any thoughts?