Whilst these guidelines advise on the appropriate choice of specialist infant formula, breast milk remains the optimal choice for infants. This should be promoted and encouraged where it is clinically safe to do so.
Symptoms and Diagnosis
- Secondary lactose intolerance occurs following damage to the intestinal mucosa, usually occurring in infants following an infectious gastrointestinal illness. It can also occur as a result of undiagnosed conditions affecting the intestinal mucosa such as coeliac disease or inflammatory bowel disease.
- Persisting symptoms suggestive of lactose intolerance include abdominal bloating, increased (explosive) wind and loose green stools for more than 2 weeks. If any other symptoms are present, including atopy or family history of atopy, consider alternative diagnosis e.g. CMPA.
- Lactose intolerance is rare in breast fed infants so an alternative diagnosis should be considered.
- Resolution of symptoms within 48 hours of excluding lactose confirms the diagnosis.
- Primary lactose intolerance which is due to an inadequate production of the lactase enzyme is rare in infants and generally a condition of older childhood or adulthood.
Onward Referral
Refer to the paediatric dietitian if the child is weaned and a milk free diet is required. Please see referral section for details of referral information in your local borough.
Treatment
- Breast feeding should continue and a lactose free maternal diet is not required. A breastfeeding assessment by a trained professional may be beneficial. Symptoms should resolve on their own within 8 weeks as the intestinal mucosa heals.
- If symptoms are causing distress, treat formula fed infants with an over-the-counter lactose free formula (see list below) for up to 8 weeks to allow symptoms to resolve.
- In infants who have started solids, lactose free formula should be used in conjunction with a lactose free diet.
- Review after 48 hours of starting lactose free formula or milk. Resolution of symptoms confirms the diagnosis. If no improvement, consider alternative diagnosis.
- Reintroduce standard formula and/or milk products after 8 weeks. If symptoms reoccur, return to lactose free formula or milk and reintroduce lactose more slowly.
- In children over 1 year of age who previously tolerated cow’s milk, lactose free formula is not required. Suggest the use of lactose free full fat cows’ milk, or a calcium fortified plant-based alternative (see SWL ‘Dairy Free Products Guide’), which can be purchased from supermarkets.
Choice of Formula
Lactose Free Formula (to be bought over the counter):
SMA® LF
Birth to 18 months (see treatment note above for those over 1 year).
Aptamil® Lactose Free
Birth to 12 months.