I'm really sorry to rain on your parade but I think you'll be fighting a losing battle. I, like you, have been prescribed inhalers in the past. I visited my doctor who wrote a strongly worded letter to my local AFCO advising that it was very unlikely that I have, or ever had, asthma and that the inhalers prescribed were purely precautionary. I was fairly confident that the RAF would at least give me a medical but alas they did not. It seems that any mention of inhaler in your history (after the age of 4) or indeed any history of wheeze pretty much bars you from any form of entry into the service.
My only option now is to try the RN although it seems that the FAA has now been decimated. I think I'll give up trying and head for Australia to be a lawyer there instead. The RAF's/RN's loss is the legal profession's/Australia's gain!