The vast majority of upper respiratory infections (URI), including sinusitis and bronchitis, are caused by viruses. In most cases an antibiotic is not warranted unless symptoms persist beyond 10-14 days, are accompanied by a fever, or symptoms continue to worsen rather than improve after several days. Most URIs will resolve within 1-2 weeks without treatment, and an antibiotic will not speed recovery. It is a myth that colored phlegm and mucous are caused only by bacteria; viruses will produce similar symptoms.
Parkway Medical recommend supportive care for cold symptoms, including antihistamines, decongestants, expectorants, fluids, etc. Medical care should be sought for worsening symptoms, fevers, shortness of breath, or symptoms lasting more than two weeks.
