Symptoms of cystic fibrosis are usually caused by the production of thick, sticky mucus throughout the body. Symptoms vary from person to person. They aren't always obvious in childhood.

Early symptoms

Symptoms of cystic fibrosis in a baby or young child may include:

• A blocked small intestine at birth.
• Unusual bowel movements.
  • The child may have diarrhea that doesn't go away, large and greasy stools, very smelly stools, or constipation.
  • If the intestines get blocked, the child's belly may stick out. The child may not be able to have a bowel movement.
• Salty sweat or skin.
• Wanting to eat more or less than normal, having little energy, or losing weight.
• Breathing problems or getting tired easily while playing.
• A cough that doesn't go away or wheezing.

As symptoms get worse

Over time, symptoms may get worse and cause problems such as:

• Coughing up mucus that sometimes has blood in it.
• Trouble exercising or not being able to exercise.
• Rectal prolapse. This means that part of the rectum sticks out from the anus.

Later symptoms

More symptoms may develop during late childhood or early adulthood. They include:

• Clubbing (rounding and flattening) of the fingers.
• Growths (polyps) in the nose or sinuses.
• Not being able to have children (infertility).