Complications of Down's syndrome 

Some children with Down's syndrome have very few health problems as a result of their condition. Others will experience several of the more common health conditions and will need extra medical care and attention.

Your child will usually need to be checked by a paediatrician more often than other children to pick up developing problems as early as possible. If you have any concerns about your child's health, discuss them with your GP, health visitor or paediatrician.

Some of the main complications associated with Down's syndrome are outlined below.

Heart problems

Around half of children with Down's syndrome are born with a congenital heart defect.

The most common defect to affect children with Down's syndrome is a septal defect. This is a hole inside one of the walls that separate the four chambers of the heart, often referred to as a "hole in the heart".

It can cause a build-up of blood in one or more of the heart's chambers, which causes the heart to work harder to pump blood through the four chambers.

If your baby is diagnosed with Down's syndrome, their heart will be carefully assessed to detect any problems as soon as possible. If a problem is found, surgery will often be needed to repair the heart.

Gut problems

Many people with Down's syndrome have some sort of problem with their digestive system. Constipation, diarrhoea and indigestion are all common, as are more serious problems such as small bowel obstruction, which stops food passing from the stomach into the large bowel.

Some children also develop coeliac disease (a condition where a person has an adverse reaction to gluten) and reflux (bringing up milk during or shortly after feeding).

Conditions such as imperforate anus (where a baby is born without an anal opening) or Hirschsprung's disease (where the large bowel is unable to push faeces towards the anus) are rare, but slightly more common in children with Down's syndrome.

Hearing problems

Most people with Down's syndrome have problems with their hearing. This is often temporary, but it can sometimes be permanent.

Glue ear (a build-up of fluid in the middle ear) is a common cause of temporary hearing problems in people with Down's syndrome.

If your child has glue ear, they will usually be referred to an ear, nose and throat (ENT) specialist for further assessment. For some children, glue ear can be treated with minor surgery, which involves placing small tubes called grommets in the ear to help drain away the fluid.

Vision problems

Many people with Down's syndrome also have problems with their eyesight and often need to wear glasses.

Common eye problems include:

  • short-sightedness – where distant objects appear blurred
  • long-sightedness – where nearby objects appear blurred
  • squint
  • eye infections, such as conjunctivitisuveitis or blepharitis
  • cataracts – where the lens (the transparent structure that sits just behind your pupil) clouds over
  • nystagmus – where the eyes move uncontrollably, usually from side to side
  • keratoconus – where the cornea (clear outer layer at the front of the eyeball) becomes thin and bulges out
  • glaucoma – increased pressure in the eye

Thyroid problems

Around one in 10 people with Down's syndrome have problems with their thyroid gland. The thyroid gland is located in the neck and is responsible for controlling your metabolism (the rate at which your body uses up energy). It does this by releasing thyroid hormones into the body.

Most people with Down's syndrome who have a problem with their thyroid have hypothyroidism, which means their thyroid gland is underactive. Symptoms of an underactive thyroid gland can include:

  • lethargy (lack of energy)
  • weight gain
  • slow physical and mental reactions

Thyroid problems will usually be picked up during blood tests and can often be treated with medication to replace the lack of thyroid hormone in the body.

Increased risk of infections

People with Down's syndrome are more likely to develop infections, such as the lung infection pneumonia, because their immune system (the body's natural defence against infection) has not developed properly.

To reduce the risk of infections, routine childhood vaccinations will be recommended, as may the annual flu jab.

If your child develops a bacterial infection, a course of antibiotics will usually be prescribed to treat it.


There is a tendency for people with Down's syndrome to develop dementia at a younger age than in the general population, usually from about 40 years of age onwards, although it's not inevitable that everyone with Down’s syndrome will develop it.

Possible signs of dementia include problems with short-term memory and understanding, confusion, and disorientation.

Page last reviewed: 14/01/2015

Next review due: 14/01/2017