Cold is an infection of the nose and upper airways caused by a germ (virus). They are extremely common. An adult can expect 2-4 colds a year and a child can expect about 5-6 colds a year. Very young children in nursery school may get as many as 12 colds a year. Many different viruses can cause a cold. This is why colds come back (recur) and immunisation against colds is not possible.

Infections of the throat , or the main airway (trachea), or the airways going into the lungs (bronchi) are also common. These infections are sometimes called  pharyngitis, laryngitis, tracheitis, or bronchitis. Doctors often just use the term upper respiratory tract infection (URTI) to include any, or all, of these infections. Most URTIs are due to a viral infection.

What are the symptoms of the common cold?

The common symptoms of a cold are a blocked (congested) nose, a runny nose, coughing or sneezing. At first there is a clear discharge (mucus) from the nose. This often becomes thick and yellow/green after 2-3 days. It may be difficult to sleep due to a blocked nose. You may feel generally unwell and tired and you may develop a cough or a mildly high temperature (a mild fever).

In other upper respiratory tract infections (URTIs), cough is usually the main symptom. Other symptoms of a cold include fever, headache, aches and pains.

How long does the common cold last?

Cold symptoms are typically at their worst after 2-3 days and then gradually clear. However, the cough may carry on after the infection has gone. This is because swelling (inflammation) in the airways, caused by the infection, can take a while to settle. It may take 2-3 weeks, after other symptoms have gone, for a cough to clear completely.

How to treat the common cold

A main aim of treatment for the common cold or most other upper respiratory tract infections (URTI) is to ease symptoms whilst your immune system clears the infection. One or more of the following may be helpful:

Taking Tylenol or Advil

Tylenol and Advil will reduce a high temperature (fever) and to ease any aches, pains and headaches. Follow the instructions given with the medicine carefully and do not take more than the advised dose. Only give these medicines to children under the age of 5 years if they have a fever or appear distressed.

Having plenty to drink

If you have a fever, to prevent mild lack of fluid in the body (dehydration). As long as you do not have a fever, there is no evidence that drinking more fluid than usual makes a difference.
If you smoke, you should try to stop for good. URTIs and serious lung diseases tend to last longer in smokers

Steam inhalation

There is not very much evidence that this helps; however, some people find it useful. It is very important to be careful to avoid burns and scalds particularly with children. A safe way of inhaling steam is to sit in the bathroom with the door closed, while running a hot shower to make the room steamy.

Vapour rubs

Vapour rubs can be bought in pharmacies and supermarkets. Some people find they help with a stuffy nose. Rub the vapour on to the chest and/or back of the person with the cold, but avoid the area under the nose.

Sore throat lozenges

Sucking sore throat lozenges (available from pharmacies and supermarkets) or boiled sweets may help ease a sore throat.

Warm drinks with honey and lemon

This may help to ease a sore throat. (Do not give honey to babies less than 1 year old as it is not known if this is safe.) Similarly, gargling salt water may temporarily ease symptoms of a sore throat.

Salt (saline) nose drops

These are nose drops made of a salty solution, which may help clear a blocked nose. They are sometimes helpful for babies who are having difficulty breathing through a blocked nose as they feed. They can be bought from a pharmacy.

What about cold and flu remedies?

You can buy many other cold and cough remedies at pharmacies. These are suitable for adults and older children only.These remedies do not help fight the infection but they may be useful for certain symptoms. For example, a decongestant nasal spray may help to clear a blocked nose.

Remember that cold and cough remedies often contain several ingredients. Be careful about taking more than one remedy in case you get too much of one ingredient. For example some cold remedies contain paracetamol and a decongestant. So if you took that and paracetamol as well, you would be taking too much paracetamol, which could be dangerous.

Some cold and cough remedies may make you drowsy. This may be welcome at bedtime if you have difficulty sleeping because of your cold. However, do not drive if you are drowsy.

Using nasal sprays

If you use a spray to ease nasal congestion, do not use it for more than a few days. It can have an immediate effect to clear a blocked nose. However, the effect does not last very long. If you use a decongestant nasal spray for more than 5-7 days, you may feel that your nose is becoming more blocked. This is called a rebound effect.

The new advice is that parents and carers should no longer use over-the-counter (OTC) cough and cold medicines in children under 6. There is no evidence that they work and they can cause side-effects, such as allergic reactions, effects on sleep or hallucinations.

For 6 to 12 year olds these medicines will continue to be available but will only be sold in pharmacies, with clearer advice on the packaging and from the pharmacist. This is because the risk of side-effects is reduced in older children because they weigh more, get fewer colds and can say if the medicine is doing any good. More research is being done by industry on how well these medicines work in children aged 6-12 years.

Note: Tylenol and Advil are not classed as cough and cold medicines and can still be given to children.

What about antibiotic medicines?

Antibiotics are not usually advised if you are normally in good health. Your immune system can usually clear the infection. Antibiotics do not kill germs which are viruses. Even if a different type of germ (called a bacterium) is the cause, antibiotics usually do little to speed up recovery from the common cold.

Antibiotics may even make cold symptoms worse, as some people develop side-effects such as diarrhoea, feeling sick or a rash. Antibiotics may be prescribed if you become more unwell, or if you already have an underlying (chronic) lung disease. They may also be prescribed if a complication develops, such as pneumonia but this is unlikely to occur if you are otherwise healthy.

Supplements and home remedies for the common cold

Many research studies have been done to try to find something which cures, or prevents the common cold. So far there has been no success, although some of the studies are not of good enough quality to be certain. Currently there is no good evidence to suggest that any of the following remedies should be used:

• Garlic
• Vitamin C.
• Echinacea.
• Zinc : There is some evidence that zinc supplementation may reduce the duration of a cold by two days.

Can the common cold be prevented?

Prevention of the common cold is difficult. Many germs (viruses) can cause an upper respiratory tract infection. Also, many viruses that cause URTIs are in the air, which you cannot avoid. However, the following are suggestions that may reduce the risk of catching a cold or of passing one on, if you have one:

• If you have a cold, avoid close contact with others – for example, kissing, hugging, etc.
• If you have a URTI, wash your hands often with soap and water. Many viruses are passed on by touch, especially from hands that are contaminated with a virus.
• Avoid sharing towels, flannels, etc, if you have a URTI, or with anyone who has a URTI.
• For children, discourage the sharing of toys belonging to a child with a URTI. If your child has a URTI, consider washing toys with soapy water after use.
• During your illness, it is advisable to avoid visiting a doctor’s office to prevent spreading germs to other vulnerable patients who might be present at the clinic

Basically, common sense and good hygiene may prevent the passing on of some viruses that cause URTIs.

How long is the cold contagious?

Most people with the common cold will be infectious for around two weeks. However, symptoms are usually worse during the first 2-3 days, which is when they’re most likely to spread the cold.

When to call your doctor

Call your doctor office if symptoms do not start to ease within two weeks, or if you suspect that a complication is developing. In particular:

• If high temperature (fever), wheezing or headaches become worse or severe
• If you develop fast breathing, shortness of breath, or chest pains.
• If you cough up blood or if your phlegm (sputum) becomes dark or rusty-coloured.
• If you become drowsy or confused.
• If a cough persists for longer than 3-4 weeks.
• If you have returning (recurring) URTIs.