Noonan syndrome

Noonan syndrome is a genetic condition that can cause a range of features, including distinctive facial features, short height, heart problems from birth (such as pulmonary valve stenosis), and some learning difficulties. It can be inherited from a parent or happen for the first time in a child. Signs vary a lot between people.

Last updated Nov 9, 2026

What it is

Heart checks, growth monitoring, and support with feeding, development and learning are usually needed.

Some children are treated with growth hormone, and heart problems may need surgery.

Common signs

  • Wide-set eyes and low-set ears
  • Short height
  • Heart problems from birth
  • A broad or webbed neck
  • Bleeding or bruising easily
  • Feeding difficulties in babies

How it is usually diagnosed

  • Examination
  • Genetic testing
  • Echocardiogram

Records worth keeping

Keeping these together makes each appointment easier, especially when you see a new doctor:

  • Genetic test results
  • Echocardiogram reports
  • Growth charts
  • Paediatric and cardiology letters

Questions to ask your doctor

  • How will my child's heart be monitored?
  • Would growth hormone help?
  • Should other family members be tested?

When to get help right away

Call 112 or go to the nearest emergency department if you have:

  • Breathlessness, blue lips or fainting, or bleeding that will not stop: get urgent medical help

This page is general information. It is not a diagnosis and does not replace a doctor who knows your history. Medfold keeps your records organised; it does not interpret them.

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