Common Cold

After an incubation period of 24 to 72 hours, cold symptoms begin with a scratchy or sore throat, followed by sneezing, rhinorrhea, nasal congestion, and malaise (1). There may be an associated headache or mild myalgia. Body temperature is usually normal, particularly when the pathogen is a rhinovirus or coronavirus. Nasal secretions are watery and profuse during the first days but may occasionally become more mucoid and purulent. Mucopurulent secretions do not indicate a bacterial superinfection. Cough is usually mild but often lasts into the second week. Infrequently, a low-grade fever may occur in older children and adults. Most symptoms due to uncomplicated colds resolve within 10 days.

Colds may exacerbate asthma and chronic bronchitis.

Purulent sputum is unusual with rhinovirus infection. Purulent sinusitis and otitis media may result from either the viral infection itself or from secondary bacterial infection. Rhinoviral pneumonia is infrequent in immunocompetent people.

• History and physical examination

• Sometimes confirmatory testing (eg, rapid antigen-detection tests, molecular diagnostic methods)

The diagnosis of the common cold is primarily clinical and presumptive (ie, specific infections may be suspected based on patient presentation, season of occurrence, knowledge of local epidemiology patterns). Allergic rhinitis is the most important differential diagnosis.

Molecular diagnostic tests, such as polymerase chain reaction (PCR) testing, are available in many multiplex panels. Confirmatory testing may be considered in patients for whom knowing the specific pathogen will affect clinical management, such as when specific antiviral therapy is indicated (eg, suspected influenza, COVID-19, or RSV) (1).

• Symptomatic treatment

The treatment of common colds is supportive. Antipyretics and analgesics may relieve fever and sore throat.

Symptomatic treatment of nasal congestion, rhinorrhea, fever and/or pain is typically with decongestants (nasal or oral) or with oral antihistamines or nonsteroidal anti-inflammatory drugs (NSAIDs). Combination therapy with antihistamines, decongestants, and analgesics may provide limited symptom relief for common colds in adults and older children; however, data are limited (1), and use must be weighed against the possibility of adverse effects.

As monotherapy, topical nasal decongestants may subjectively be effective in adults, but the use of topical medications for > 3 to 5 days may result in rebound congestion (rhinitis medicamentosa) (2). The efficacy of oral versus topical nasal decongestants have yet to be conclusively established.

Medications containing anticholinergic properties may be effective for the treatment of rhinorrhea. These medications include first-generation oral antihistamines that have anticholinergic activity (eg, chlorpheniramine) and intranasal ipratropium bromide (2 sprays of a 0.03% solution 2 or 3 times a day); however, both medications offer minimal benefit in the short term and should be used with caution in older adults, people with benign prostatic hypertrophy, or people with angle-closure glaucoma (3, 4). First-generation antihistamines frequently cause sedation.

Zinc (5), echinacea (6), and vitamin C (7) have all been evaluated as common cold therapies, but none has been clearly shown to be beneficial. Although zinc lozenges may reduce the duration of common cold symptoms, that benefit must be balanced against adverse effects, notably a bad taste and nausea (5). Importantly, there is concern about permanent anosmia with use of intranasal zinc (8). Honey may relieve symptoms of cough in children > 1 year of age but should be avoided in children < 1 year of age because of the risk of infant botulism (9).

Cough syrups, cough suppressants, and expectorants are not routinely recommended because findings have been inconsistent, and the quality of evidence supporting their use is low (10).

Antibiotics should not be given for the common cold; they are given only for other indications, with clear evidence of secondary bacterial infection (11). Intranasal antihistamines and intranasal glucocorticoids have not shown benefit. Oral second-generation (nonsedating) antihistamines are similarly ineffective for treating the common cold. Oral phenylephrine is also unlikely to be effective when used as a decongestant (12). Antihistamines and decongestants are not recommended for children < 4 years of age.

Vaccinations for some viruses (eg, RSV, influenza, COVID-19) are available but have limited efficacy in the prevention of nonsevere manifestations of an infection such as the common cold (1).

Measures to prevent spread of the common cold include handwashing, avoiding close contact with people with a cold, covering the mouth and nose when coughing or sneezing, and using a surface disinfectant in a contaminated environment.