Cystic fibrosis factsheet


Cystic fibrosis is a genetic condition that mainly affects the lungs and digestive system. It causes thick, sticky mucus to develop, which can cause infections and problems with digesting food.

Genetic conditions are caused by a change in a particular gene that gets passed down from parents to children. 

In cystic fibrosis, there is a change to the gene that helps to control the amount of salt and water in cells. This makes mucus in the lungs and digestive system thicker and sticker than normal.

Cystic fibrosis is the most common genetic condition in Australia. While there is currently no cure, new treatments are being developed that are improving the lives of babies, children, and adults with cystic fibrosis.

 Signs and symptoms

Symptoms of cystic fibrosis can be different for each child.

Some general symptoms include:

  • a cough with thick, sticky mucus
  • weight loss or slow weight gain
  • excess wind and bloating
  • constant hunger or frequent feeding
  • babies being irritable and difficult to settle between feeds
  • poos that are: 
    • frequent
    • large
    • loose
    • explosive
    • foul smelling
    • oily or greasy.


Cystic fibrosis can be found by doing:

  • a screening and diagnostic test during pregnancy
  • the neonatal screening or "heel-prick test" after your baby is born
  • a sweat test and a genetic blood test for children showing symptoms or with a positive result on the heel-prick test.

Parents can also be tested before pregnancy to find out whether they carry a gene that causes cystic fibrosis.

Carrier screening

Cystic fibrosis can only happen when a baby inherits two cystic fibrosis genes, one from each parent. A carrier is a person who inherits only one cystic fibrosis gene from one parent.

Carrier screening tests are blood tests. They are the only way to know whether you have a cystic fibrosis gene. Many people will not know they have a cystic fibrosis gene until they do the screening test before planning to get pregnant or during pregnancy.

Carrier screening tests are offered to anyone pregnant or seeing a doctor to plan a pregnancy. 

It is your choice whether to do the carrier screening test or not. Speak to your local doctor about carrier screening tests if you have any questions or concerns.

Tests during pregnancy

Tests can be done during pregnancy to find out whether a baby has cystic fibrosis or is a carrier of a cystic fibrosis gene.

These tests can include:

  • chorionic villus sampling: done between 11 -12 weeks of pregnancy, a small sample of tissue is taken from the placenta and tested
  • amniocentesis: a sample of the fluid surrounding your baby is collected by a needle for testing. 

These tests are optional but may be recommended if you have a family history of cystic fibrosis or if one parent carries a cystic fibrosis gene.

Speak to your local doctor about tests during pregnancy if you have any questions or concerns.

Neonatal screening test

Newborn babies will have the neonatal screening test on the third day after birth. This test is also known as the "heel prick" screening test.

A small needle is used to prick the bottom of the baby's heel, and a card is pressed to the droplet of blood. This card is then sent off to be tested for a range of disorders, including cystic fibrosis.

The neonatal screening test can pick up approximately 90% of babies born with cystic fibrosis.

If cystic fibrosis is picked up on the neonatal screening test, your baby will need more tests to diagnose the condition. Speak to your doctor or nurse in the hospital if you have any concerns about the neonatal screening test for your baby.

Sweat and blood tests

Other tests to diagnose cystic fibrosis after a child is born include:


While there is currently no cure for cystic fibrosis, treatments are always improving.

Children with cystic fibrosis will usually have a team of health professionals that look after them, including:

  • respiratory paediatrician
  • nurse
  • physiotherapist
  • dietician
  • respiratory scientist
  • social worker
  • psychologist.

Every child is different, so the number of appointments and treatments will depend on each child's needs.

Common treatments for cystic fibrosis include:

CFTR modulator medications

CFTR modulators are a type of medication that is used to treat cystic fibrosis. These medications target the problem in the cystic fibrosis gene, improving the levels of fluid and salt that go in and out of the cells.

Speak to your child's treatment team for more information about CFTR modulator medications. 

Chest physiotherapy

Children with cystic fibrosis are more at risk of infection and damage to the lungs from sticky mucus building up. 

Your child may need chest physiotherapy to help keep their airways clear. A specialised physiotherapist will work with your child on a plan that is right for their needs as they grow and develop.

Nutrition support

Digestive enzymes

Around 85% of all children born with cystic fibrosis will have a condition called pancreatic insufficiency. This condition happens when the pancreas does not make enough digestive enzymes. Digestive enzymes break down food into nutrients that the body can absorb. 

Children with pancreatic insufficiency need a treatment called pancreatic enzyme replacement therapy (PERT). PERT is when a child is given enzymes before eating to help digest food and absorb nutrients. Creon is the most used brand of enzymes in Australia.

Vitamins and minerals

Children with cystic fibrosis may also need extra vitamins and minerals. A special multivitamin called vitABDECK is made especially for children with Cystic fibrosis. 


Children with cystic fibrosis will also lose more salt in their sweat than other children. This can put them at risk of dehydration. Your child's treatment team will work with you to make sure your child has enough salt in their diet.

Last updated Tuesday 5th March 2024