Thank you for your inquiry.
There is evidence in the literature that some dry powder inhalers can be contaminated with milk allergen (see references noted below). This can be avoided simply by using metered-dose inhalers propelled by hydrofluoroalkane (HFA). Examples would be beclomethasone HFA and fluticasone HFA. If one is worried about possible adverse reactions due to milk contamination, then it is advisable to use the aerosol inhalers such as those mentioned above.
Thank you again for your inquiry and we hope this response is helpful to you.
J Allergy Clin Immunol. 2004 Mar;113(3):558-60. Contamination of dry powder inhalers for asthma with milk proteins containing lactose. Nowak-Wegrzyn A, Shapiro GG, Beyer K, Bardina L, Sampson HA.
Child Health Alert. 2005 Jan;23:1-2. Asthma inhalers may pose risks in the milk-allergic child.
Phil Lieberman, M.D.