Medical Encyclopaedia › Common cold (short definition)
In brief: A cold is a harmless viral infection of the upper respiratory tract. Adults catch two to four colds a year, children even more often. The symptoms usually subside by themselves after seven to ten days.
Course and symptoms
A cold often begins with a scratchy throat, followed by a runny nose, blocked nose, sneezing and later a cough. Mild fever, headache and aching limbs are possible. The cough can persist for a few weeks after the other symptoms have subsided.
Cold or flu?
True flu (influenza) usually begins suddenly with high fever, severe muscle aches and headache and a pronounced feeling of illness. A cold, by contrast, develops more slowly and is milder.
What can bring relief
There are no medicines that act against the cause of cold viruses; antibiotics do not help. Rest and sufficient fluids support recovery. Decongestant nasal sprays make breathing easier but should be used for no longer than about a week. Saline solutions moisten the nasal mucosa. Painkillers such as ibuprofen or paracetamol relieve sore throat and headache. For a cough, expectorants or, in the case of a distressing dry cough, cough suppressants may be considered depending on the type. Many herbal preparations are available; their effectiveness is supported to varying degrees.
Warning signs
Medical advice is needed for fever above 39 °C or lasting longer than three days, shortness of breath, severe ear or facial pain, symptoms that worsen again after an initial improvement, and for infants, older people and those with chronic illnesses.
Related terms in the encyclopaedia
Rhinitis, Flu, Sinusitis, Nasal spray, Cough syrup, Expectorant, Lozenges
Sources
- Deutsche Gesellschaft für Allgemeinmedizin und Familienmedizin (DEGAM): S3-Leitlinie Akuter und chronischer Husten
- IQWiG: gesundheitsinformation.de – Gesundheitsinformationen des Instituts für Qualität und Wirtschaftlichkeit im Gesundheitswesen
- Bundesministerium für Gesundheit: gesund.bund.de – Nationales Gesundheitsportal
Note: This article is for general information and does not replace advice, diagnosis or treatment from a doctor or pharmacist. Last updated: October 2026.