Middle ear infection (otitis media) is an infection of the part of the ear inside the ear drum. It causes ear pain and fever, is most common in children, and often follows a cold.

• The main symptom is pain in the ear.
• Sometimes the ear drum may burst causing a discharge of fluid from the ear. (Incidentally, this releases the pressure behind the ear drum and therefore the pain usually disappears.)
• Many children vomit when they have a feverish illness, and so may be sick with middle ear infection.
• There may be some decrease in hearing.
• Occasionally people become a little dizzy.

The whole infection usually only lasts a few days, but there may be persisting deafness for up to a few weeks after the infection.

A cold or other infection of the upper airways causes the tubes that drain the ears in to the back of the throat to become swollen and filled with mucus or catarrh. These tubes are called eustachian tubes, and are the tubes we open, by yawning or swallowing, to stop our ears popping as we go up a hill or in a plane.

This swelling may block the eustachian tubes and stop the normal drainage of fluid from the middle ear down to the back of the throat. As water which is stagnant becomes foul, so there is more chance of germs building up in this stagnant situation in the middle ear, and a middle ear infection (acute otitis media) is the result.

Otitis media is most likely to happen in children because their eustachian tubes are narrower to start off with. Sometimes the glandular tissue at the lower end of the eustachian tubes (the adenoids) seems rather more enlarged than in other children, making blockage of the tubes even more likely. However it can happen in anybody.

In someone (especially a child) who has had a cold or sore throat, who suddenly seems to get worse, with ear pain and usually a fever, then it is likely that otitis media is the diagnosis.

However other things can appear in the same way and it is wise see your doctor (or sometimes nurse), who will look in the ear with a special flashlight known as an auriscope or otoscope.

It is wise to see your doctor. This can usually safely wait until daytime.

The treatment, however, can start immediately, as the most important part is to reduce the pain. For this, acetaminophen (paracetamol) either as a liquid, a tablet, or a soluble tablet is usually the best. Ibuprofen, a NSAID is another alternative. You should not use aspirin in a child under the age of 16, but it can be very helpful for the older age groups.

In many countries the standard treatment for otitis media has been a course of antibiotics. There is currently some debate as to whether this should indeed be the treatment. There are points for and against their use.

There is no "right" and "wrong" approach, but your doctor is likely to weigh up the individual circumstances, bearing in mind your wishes. There are some things, such as a chest or other infection at the same time, that increase the likelihood that your doctor will prescribe antibiotics. Your doctor may prescribe an antibiotic to use if things get worse or there is no improvement after 1-3 days.

Sometimes people raise the question of operations, for example removal of the adenoids (adenoidectomy) when children keep suffering from attacks of otitis media. In most circumstances the child, who seems to be going through a series of infections, will literally grow out of it, as he or she gets bigger and the eustachian tubes grow wider. It is thus usually worth holding on.

However you should discuss the problem and your concerns with your doctor, who may want to ask a specialist for advice.

• Points for and against the use of antibiotics to treat middle ear infection