A cold is an infection caused by a virus. It’s a common and usually mild illness that affects the nose and throat. 
 
How a cold develops
About colds
Symptoms of a cold
Complications of a cold
Causes of a cold
Diagnosis of a cold
Treatment of a cold
Prevention of a cold
 

How a cold develops

 

 

About colds

Colds can be caused by hundreds of different types of virus. About half of all colds are cause by rhinoviruses.
 
On average, adults have two to five colds each year and school-age children can have up to eight colds a year. Adults who come into contact with children tend to get more colds. This is because children usually carry more of the virus, for longer.
 
In the UK, you’re more likely to get a cold during the winter months although the reasons why aren’t fully understood at present.
 

Symptoms of a cold

The cold virus grows in the soft, warm surfaces of your nose, throat and sinuses, so this is where you usually get symptoms. The first symptom is often a sore or irritated throat. The main symptoms of a cold in adults and older children are:
 

  • a blocked nose
  • sneezing or a runny nose 
  • cough
  • headache
  • muscle pain
  • earache
  • sinus pain
  • feeling generally tired

 
Young children and babies may have other symptoms, including:
 

  • problems feeding
  • being restless or irritable
  • a fever
  • swollen glands in the neck

 
If your child has a blocked nose, it may interfere with their breathing and sleeping.
 
Symptoms usually start within one or two days of becoming infected and last for about a week. Sometimes symptoms can last for up to two weeks.
 

Complications of a cold

Most colds are mild and don’t cause any other health problems. However, on rare occasions, a cold can lead to complications. In adults and older children it may lead to:
 

  • inflammation of your sinuses (sinusitis), which can cause pain in your face and head
  • a chest infection or pneumonia – this is more common if you are older, a smoker or have a medical condition that affects your immune system
  • worsening of asthma

 
In young children, middle-ear infections are the most common complication of a cold. Very young children and babies may develop a chest infection, pneumonia or croup.
 

Causes of a cold

You can catch a cold from close personal contact with someone who is infected with the virus.
 
The cold virus is spread by droplets when someone coughs or sneezes. You can also catch a cold from direct contact with someone who has one, for example by shaking hands or by touching something they have recently touched. You pick up the cold virus on your hands and then, when you touch your nose or mouth, you may pass the virus to yourself.
 

Diagnosis of a cold

Most people are able to diagnose themselves or their children as having a cold and won’t need to see their GP. However, if you’re worried that your symptoms are more severe or not getting better, see your GP.
 

Treatment of a cold

For most people, a cold will get better on its own within a week of the symptoms starting without any specific treatment. However, there are treatments that can help to ease your symptoms and make you feel more comfortable. These are available from your pharmacy, which means that you can treat yourself, rather than needing to see your GP.
 
There is no cure for colds. Antibiotics, which treat infections caused by bacteria, don't work on cold viruses.
 

Self-help

There are a number of self-help measures that may help to ease the symptoms of a cold.
 

  • Drinking enough fluids to prevent dehydration.
  • Steam inhalations with menthol, salt water nasal sprays or drops may be helpful.
  • Vapour rubs may help relieve symptoms for children.
  • Hot drinks (particularly with lemon), hot soups and spicy foods can help to ease irritation and pain in your throat. 
  • Sucking sweets or lozenges which contain menthol or eucalyptus may sooth your throat.
  • Gargling with salt water may help a sore throat.

 
You should try to make sure you get enough rest if you have a cold. It’s not usually necessary to stay off work or school.
 

Medicines

If you have muscle pains, a headache, sinus pain or a sore throat, you can take paracetamol or ibuprofen as a painkiller. These medicines will also help to reduce a fever if you have one.
 
It’s important to check the dose you're taking of different types of medicine. It's easy to accidentally have more than the daily dose when using more than one product, for example tablets, capsules and a hot lemon drink that contain the same active ingredient, such as paracetamol.
 
Children can take paracetamol or ibuprofen as a liquid. Talk to your pharmacist about which painkillers are suitable for your child.
 
If you have a blocked nose or sinuses, decongestant tablets may help to ease the symptoms. Nasal sprays can also give you relief from a blocked nose for a few hours but if you use them for too long, they can cause rebound congestion. Decongestants shouldn’t be given to children under the age of six and shouldn’t be taken if you take a medicine to reduce your blood pressure.
 
Some people find cough medicines helpful, though they are unlikely to be effective in treating the symptoms of a common cold. Glycerine, honey and lemon can be used for children under the age of six.
 
Always read the patient information leaflet that comes with your medicine and if you have any questions, ask your pharmacist for advice.
 

Complementary medicines

There are a number of supplements and complementary medicines that are popular for preventing and treating colds. These include vitamin C, menthol, zinc, garlic and Echinacea. 
 
Menthol can help to ease a blocked nose because it has a cooling sensation. It can also help to relieve the symptoms of a sore throat and cough because it contains a local anaesthetic which numbs the area.
 
There is not enough evidence to suggest that taking vitamin C, zinc lozenges or garlic or Echinacea are likely to be effective at treating a cold.
 
Complementary medicines can interact with other medicines, so you should always tell your doctor or pharmacist about all of the medicines you’re taking.
 

Prevention of a cold

The viruses that cause a cold are very common so it can be very difficult to prevent a cold.
 
Cold viruses are often passed on by direct contact so, if someone has a cold you may be able to stop it spreading by maintaining good hygiene. For example, don’t share towels, do wash your hands in hot soapy water and clean surfaces such as door handles or toys that have been touched by the person who has the cold.
 

This section contains answers to common questions about this topic. Questions have been suggested by health professionals, website feedback and requests via email.
 
Why isn't there a cure for the common cold?
Is being stressed linked to catching a cold?
How long will I be infectious for? 

Why isn't there a cure for the common cold?

There isn't a cure for the common cold because it's difficult to produce a vaccine or medicine that protects against all the different types of cold virus.
 

Explanation

Colds are very common and most people will have at least one cold every year. This is because there are at least 200 different viruses that can cause a cold. The rhinovirus is the most common and there are more than 100 different types of this virus. So, even if your body develops immunity to one type of virus, a different one can give you another cold. This is why scientists haven’t yet been able to develop a vaccine or medicines to prevent a cold.
 

Is being stressed linked to catching a cold?

Yes. You’re more likely to get a cold if you’re under stress.
 

Explanation

There is a link between stress and how likely you are to get an infection. Research suggests that if you’re under stress in your day-to-day life then you’re more likely to develop an infection than someone who isn’t stressed. This means that you’re more likely to catch a cold and develop symptoms if you’re stressed.
 
Doctors don’t yet know exactly why stress may make you more likely to develop infections, but it’s thought that it affects how well your immune system works to fight off infection.
 

How long will I be infectious for?

You’re at your most infectious during the first two or three days of a cold, when you are sneezing and have a cough and a runny nose. Although your symptoms will go within a week or two, you can remain infectious for several weeks.
 

Explanation

When you catch the cold virus from someone, it usually takes about two days for you develop symptoms. You will be most infectious at the start of a cold when you have symptoms such as a runny nose, cough and sneezing. This is because you can pass the virus on by coughing and sneezing as well as by direct contact, for example when you blow your nose the virus will be on your hands. 
 
Your symptoms are likely to be at their worst during the first two or three days of a cold and then you should gradually start to feel better. Most adults and older children usually have symptoms for about a week, in younger children symptoms can last for up to two weeks. However, you can remain infectious for several weeks.

Further information

Sources
 

  • Common cold. Clinical Knowledge Summaries. www.cks.nhs.uk, published May 2007.
  • Common cold centre. Cardiff University. www.cardiff.ac.uk, accessed 1 September 2010
  • Common cold medications. Cardiff University. www.cardiff.ac.uk, accessed 2 September 2010
  • Arroll B, Kenealy T. Antibiotics for the common cold and acute purulent rhinitis. Cochrane Database of Systematic Reviews. 2005, Issue 3. doi: 10.1002/14651858.CD000247.pub2.
  • Aspirin. Joint Formulary Committee, British National Formulary. 55th ed. London: British Medical Association and Royal Pharmaceutical Society of Great Britain, 2010
  • Common cold. Clinical Evidence. www.clinicalevidence.bmj.com, published June 2008.

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