Information for children, teenagers and families


All children need good nutrition to grow and develop. This is particularly important in children with Cystic Fibrosis because a good body weight can help to fight chest infections. The exact nutritional requirement varies depending on age, sex and from person to person. However, children with Cystic Fibrosis normally require more food than their peers due to:

  • Chest infections which means their body works harder and therefore needs more energy
  • Not absorbing all the energy from their food the Pancreatic Enzyme Therapy is not as good as enzymes that are produced by our bodies

A Dietitian is available at every clinic, annual review and during inpatient stays. Our role is to help your child grow and to support you and your child to manage their dietary treatment. We can also be contacted by telephone or email.

The following links contains further useful nutrition ideas provided by the CF Trust:

Nutrition: Eating well. click: here

Fact sheets: "Nutrition: a guide for children and parents" and "Nutrition: a guide for feeding infants" click: here

Pancreatic Enzyme Replacement Therapy (PERT)

Approximately 90% of patients with cystic fibrosis have pancreatic insufficiency. The commonest way to test for this is to send a stool for faecal elastase. Most patients with pancreatic-insufficient CF will have an elastase level of <15 mcg/g stool. All pancreatic insufficient patients require PERT; PERT is given for all foods that contain fat.

Some patients are initially pancreatic sufficient may become insufficient over time. Any pancreatic-sufficient patients who have had a change in gastrointestinal symptoms or problems with weight gain should have a stool sent for repeat elastase levels.

There are several available PERT formulations but Creon is the commonest enzyme supplement used and comes as the following preparations

Creon Micro 500050003600200
Creon 10,00010,0008000600
Creon 25,00025,000180001000

The usual starting dose for newborn screened infants is half a scoop of Creon micro (5000 lipase units per scoop) with each feed. The dose is then adjusted according to fat intake, weight gain, and signs of malabsorption (such as abdominal pain and bloating and/or loose, oily stools). There are no specific guidelines for enzyme dosing and this is decided on an individual basis according to reported symptoms and a dietary record. The dose required varies widely and most experienced parents and older children become very capable at judging their own enzyme requirements based on what they are eating (and specifically their fat intake). The usual dose range is one Creon 10,000 capsule for between 3 and 8 grams of fat. Inevitably the dose of Creon increases as children get older and their appetites increase.

All PERT should be enteric coated and enzyme capsules should be swallowed whole and not chewed. Babies are usually given their Creon with a spoon of apple sauce. It is important that PERT is not mixed in with a bottle or meal as the enzymes will be activated before they reach the small intestine. Generally PERT is taken at the beginning of a meal but it will often need to be taken in the middle of a meal or between courses.

Enzyme administration may need to be altered in some situations e.g. if a naso-gastric tube is being used or if a patient is nil by mouth. This should be discussed with the CF team.

Doses of PERT ideally will not exceed 10,000 lipase units/kg/day (but often they will do). This is because high doses of PERT have historically been associated with fibrosing colonopathy, but this complication is rarely seen today. The clinical situation should be reviewed in all patients who require high PERT dosing; a proton pump inhibitor will often be started if there are ongoing signs of malabsorption.

Things to consider if malabsorption persists:

  • Are the enzymes in date?
  • Are the enzymes being stored correctly (e.g. out of sunlight)?
  • Are the enzymes being taken correctly and at the correct times in relation to meals?
  • Are children avoiding or forgetting to take their creon?
  • Are there any other pathologies such as coeliac disease?