[6] Acute URTIs include rhinitis, pharyngitis/tonsillitis, and laryngitis often referred to as a common cold, and their complications: sinusitis, ear infection, and sometimes bronchitis (though bronchi are generally classified as part of the lower respiratory tract.)

Symptoms of URTIs commonly include cough, sore throat, runny nose, nasal congestion, headache, low-grade fever, facial pressure, and sneezing.

[6] Color or consistency changes in mucous discharge to yellow, thick, or green are the natural course of viral URTI and not an indication for antibiotics.

[11] Other bacterial causes are Streptococcus pneumoniae, Haemophilus influenzae, Corynebacterium diphtheriae, Bordetella pertussis, and Bacillus anthracis[citation needed].

Nasopharyngitis (rhinopharyngitis or the common cold) affects the nares, pharynx, hypopharynx, uvula, and tonsils generally.

[citation needed] Treatment comprises symptomatic support usually via analgesics for headache, sore throat, and muscle aches.

[16] A 2017 systematic review found three interventions which were probably effective in reducing antibiotic use for acute respiratory infections: C-reactive protein testing, procalcitonin-guided management, and shared decision-making between physicians and patients.

Outcomes were mixed depending on the respiratory tract infection; symptoms of acute otitis media and sore throat were modestly improved with immediate antibiotics with minimal difference in complication rate.

[26][27] Mucolytics such as acetylcysteine and carbocystine are widely prescribed for upper and lower respiratory tract infection without chronic broncho-pulmonary disease.

[28] Routine supplementation with vitamin C is not justified, as it does not appear to be effective in reducing the incidence of common colds in the general population.

Some evidence exists to indicate that it could be justified in persons exposed to brief periods of severe physical exercise and/or cold environments.

[8] In the United States, URTIs are the most common infectious illness in the general population, and are the leading reasons for people missing work and school.