Can inhaled asthma medications containing lactose cause an allergic reaction in someone with a cow’s milk protein allergy? First I think it is important to clarify we are talking about two different issues:
A milk allergy is a true food allergy caused by an allergic reaction to the protein in milk. This allergy usually shows up early in life.
“Lactose intolerance,” is when there is not enough of the enzyme lactase needed to break down lactose. Lactose is the sugar in milk and other dairy products. This is more common and not as severe as a milk allergy. It may take longer to develop, and it can happen at any time.
As I researched this, I found different views. One side recommended those who have a “cow’s milk protein” allergy not use dry powder inhalers (DPIs) with lactose. The concern is that it may trigger a severe asthma attack for individuals who are “severely allergic” to cow’s milk, inhaling being far more dangerous than ingesting the same amount of milk protein. Pharmaceutical grade lactose contains small amounts of milk protein.
The other side of this issue is that lactose in DPIs is not likely to be a problem. For example, Advair diskus contains 12.5 mg lactose but 3,000 mg are needed to provide symptoms. You need to take into consideration how many times you ingested medications containing lactose along with anything else that may have been mistakenly ingested. Lactose intolerance symptoms are more likely if you have ingested multiple medications ingested.
The good news is that all pressurized, spray inhalers (MDIs) are lactose free.
Dry powder inhalers (DPIs) that do contain lactose include: Advair diskus, Flovent diskus, Foradil aerolozer capsules, Oxeze (long-acting bronchodilator) turbuhaler, Spiriva capsules, Symbicort turbuhaler, and Ventolin diskhaler, diskus, and rotacaps.
Two DPIs that are lactose-free include: Bricanyl (bronchodilator) and Pulicort (inhaled corticosteroid).
It’s important to take note: Advair diskus monograph now states “contraindicated in patients with IgE-mediated allergic reactions to lactose or milk.”
This is a good topic to bring up with your allergist! If there are comparable lactose-free alternatives, it does not hurt to choose the safer route.