Asthma inhalers may pose risks in the milk-allergic child.

Lactose is a sugar that comes from cow's milk, and it is commonly used as an inactive ingredient in many medicines, including some inhalers that are used by children with asthma. Children with asthma may also be allergic to milk, which means they are allergic to the proteins in milk, not the milk sugar (lactose). However, if a child has a very severe form of milk allergy, his or her parents may wonder whether a medicine that contains lactose may be contaminated by milk proteins, which could pose a threat to the child's health.

Recently, researchers described an 8 year-old boy with asthma and very serious milk allergy who had a severe allergic reaction after using a new container of his routine Advair Diskus, a dry powder inhaler. Traces of milk protein were found in the lactose contained in the Advair inhaler.

The researchers then looked for traces of milk protein in other lactose-containing dry powder asthma inhalers, and they also looked at lactose that was used in other medications. They found that some samples had small amounts of milk protein in them. As fluorocarbon gases are being eliminated from asthma inhalers to protect the Earth's ozone layer, many inhalers are switching to dry powder, and most of these contain lactose. Since it's hard to know which batches of lactose might contain small amounts of milk protein, the authors recommend that children with severe milk allergy try to avoid using asthma inhalers that contain lactose. (Nowak-Wegrzyn A et al; Journal of ...