Summary
What is a cold? A common cold is a viral infection of the lining of the nose, sinuses and throat. Adults commonly have several colds a year; young children may have six to ten or more because they encounter many viruses for the first time.
Symptoms: A runny or blocked nose, sore throat, cough, sneezing and headache are common. Symptoms often begin one to three days after exposure, peak during the first few days and improve within about a week, although cough and congestion can last longer. Symptoms that worsen, remain severe or fail to improve may require assessment.
Spread: Many different viruses cause colds. They spread through respiratory droplets, close contact and contaminated hands or surfaces. People can spread the virus shortly before and during their symptoms.
Cold or influenza? Influenza often starts more abruptly and is more likely to cause high fever, marked muscle aches, exhaustion and a dry cough. Symptoms overlap, and other infections can look similar.
Prevention and treatment: Hand hygiene, covering coughs and sneezes and avoiding close contact when unwell can reduce spread. Treatment is aimed at comfort. Antibiotics do not treat a viral cold.
Self-care
Rest, drink according to thirst and use paracetamol if suitable for pain or fever. Saline nasal spray or rinsing can ease dryness and congestion. A decongestant nasal spray may provide short-term relief but should generally be used for only a few days to avoid rebound blockage; ask a pharmacist or doctor whether it is safe for you. Check labels to avoid taking the same ingredient in several cold remedies.
Antibiotics are not useful for an uncomplicated cold and can cause side effects and antibiotic resistance. Yellow or green mucus alone does not prove that antibiotics are needed.
When to seek advice
Most colds resolve without complications. Contact a clinician if symptoms are severe, worsen after initial improvement, last unusually long, or if you have a condition that increases your risk. Seek urgent help for significant breathing difficulty, chest pain, confusion, dehydration, blue lips, a stiff neck or a child who is unusually drowsy or difficult to wake.
Important
This information is general and does not replace an individual medical assessment. Contact a doctor if symptoms are severe, sudden or persistent.
