Introduction Cow's milk protein (CMP) intolerance affects 2–3% of all infants and generally resolves in the first 3 to 4 years of life. A maternal CMP free diet is indicated for those breast feeding. European guidelines state ‘Infants with cow's milk protein allergy who are not breast fed should receive a dietary product with highly reduced allergenicity based on “extensively” hydrolysed protein or, in selected cases, a product based on an amino acid mixture’.1 Only about 10% of infants with CMPI require an AAF; for example, those with failure of EHF or anaphylaxis. The vast majority of these Hypoallergenic formulae are prescribed for CMPI with only a few cases for intestinal failure.

Aim We wished to study prescribing practices for such formulae throughout Wales. Methods. Data on prescribing practices for Hypoallergenic Formulae throughout Wales were obtained from NHS Wales Prescribing Services for 2009 and analysed by the 22 Local Health Board areas.

Results There were 26 971 prescriptions for specialty formula in Wales in 2009: lactose-free 7886, soya 5001, and 14 084 hypoallergenic formula-EHF 9442 and AAF 4642. The average percentage for the hypoallergenic formula prescriptions was EHF 67% and AAF 33%. However there was a huge variation between areas with the percentage of prescriptions for EHF ranging from 40–92% and AAF ranging from 8 to 60%. Only 1/22 areas had a prescribing rate for AAF of 10% or less.

Conclusion There is an eightfold variation in the prescribing of AAF within Wales which is unlikely to be due to patient variation. European guidelines are not being followed in most areas. This may have considerable clinical and financial implications.