Glue ear, grommets, and adenoids

Information for parents from the Ear Nose and Throat (ENT) Department

Your child has been diagnosed as having a problem with fluid or mucus build-up behind their ear drum. This condition is often called “glue ear”. This leaflet explains the following.

We hope this leaflet answers some of the questions you may have. If you have any further questions or concerns, please speak to a member of your child's healthcare team.

How does a normal ear and hearing work?

The normal ear is divided into three parts - outer, middle, and inner ear.

Parts of the ear
Parts of the ear
  • The inner ear acts like a microphone. It turns sound vibrations into electrical signals, which are sent to the brain via the nerve of the hearing. The inner ear is also concerned with balance. To hear normally, the eardrum and ossicles must be able to move easily.

  • For this to happen the middle ear must contain air at the same atmospheric pressure as the outer ear. The air in the middle comes from the back of the nose via the Eustachian tube.

What is glue ear?

Eustachian Tube blocked behind the ear drum
Eustachian Tube blocked behind the ear drum

Glue ear is a build-up of fluid behind the eardrum in the middle ear. The fluid may be thick and sticky or thin and watery. Both stop the eardrum and ossicles vibrating easily, so quieter sounds are not heard.

Glue ear is the most common cause of deafness in children. Other names for glue ear are:

  • middle ear effusion; and

  • chronic secretory otitis media.

What causes glue ear?

Most children get glue ear after a cold or ear infection. The Eustachian tube is small and blocks easily. It then fails to ventilate the middle ear. Sticky secretions cannot drain away, so fluid builds up in the middle ear. Movement of the eardrum and ossicles is weakened or damaged, causing partial deafness.

Most cases get better quickly after a cold. A small number continue for months or years.

The most common reasons for glue ear to continue are:

Sometimes glue ear runs in families, although it is not strictly speaking hereditary. Often no cause is found.

What are adenoids?

Adenoids are cauliflower-like swellings of immune tissue at the back of the nose. Normal adenoids help fight off infections. If they get too big they cause blockage of the nose and Eustachian tube. In severe cases they can obstruct breathing at night.

What are the symptoms of glue ear?

What are the treatment options?

What is a grommet and how does it work?

Grommet in place through the ear drum
Grommet in place through the ear drum

A grommet is a tiny plastic tube, shaped like a mini cotton reel, about 2mm across.

It is fitted through a small cut in the eardrum (myringotomy). The tension of the eardrum grips the grommet. The cotton reel shape prevents it falling in or out.

The grommet allows air from the outer ear directly into the middle ear. If the grommet remains in position and is not blocked, your child’s hearing will return to normal almost immediately. The grommet does not drain fluid out, it lets air into the middle ear.

The grommet is designed to stay in position for about 9 to 15 months. At this point, the eardrum heals over and the grommet drops out.

It is important to understand that a grommet does not cure the underlying cause of glue ear. While it is in position and working, the grommet does give highly effective and immediate relief of deafness and earaches. This buys time, and allows your child the chance to ‘grow out of it’.

If factors such as passive smoking are not dealt with, there is an increased risk that your child’s glue ear will come back once their grommets fall out.

How is the operation done?

Are there any risks?

What happens after the operation?

What about swimming and grommets?

Will fluid discharge from my child's ear after their operation?

In the first few days after their operation, there may be a slight discharge or bleeding from your child’s ear. This is normal and nothing to worry about. After that there should be no discharge. If your child's ear continues to run and is especially smelly, that means they have an ear infection.

The infection is best treated with quinolone ear drops, which can be prescribed by your GP.

If your child has grommets, antibiotics taken by mouth are not very good for treating ear infections.

What happens after the grommet comes out?

The grommet only helps while it is in your child’s eardrum and open. After it has fallen out, the eardrum heals over. In 2 out of 3 cases:

If the Eustachian tube is still blocked, the glue ear can come back. It may be necessary to operate again in 1 in 3 cases. Of patients who have a second set of grommets, about 1 in 3 will need a third (1 in 9 overall). Of those, 1 in 3 will need a fourth set (one in 227 overall), and so on.

Will my child have a follow-up appointment?

A follow-up hearing test will be arranged after 6 weeks. After that, we advise that your child sees their GP once a year to check their grommet is still in place.

Do grommets scar the eardrum?

Yes. But the scar does not have any noticeable effect on hearing. It is less of a problem than the scarring caused by repeated ear infections.

Contact details

If you have any queries or concerns, please contact one of the following.

What if I have any questions or concerns?

If you have any further queries or concerns, please speak to your doctor or consultant.

Further information

References

  1. Kay DJ, Nelson M, Rosenfeld RM. Meta-Analysis of Tympanostomy Tube Sequelae. Otolaryngology - Head and Neck Surgery April 2001; 124 (4): 374-380.

  2. Great Ormond Street Hospital for Children NHS Foundation Trust. Treatment of glue ear with grommets. Last review date September 2017.

[Web sites last accessed 28th October 2025]

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