We have gone failsafe before but I never managed to get to get to the bottom of the problem for my son’s asthma/allergic rhinitis. I knew it was food, and suspected colours and preservatives. The dietitian you recommended was very good and we had good results with the elimination diet. Because of the asthma she wouldn't challenge MSG, preservatives or colours. It turns out our son started to wheeze about day 6 of the salicylate challenge. After two days of the amine challenge we gave up because he was so ANGRY (but not wheezing). Since then we have been to an allergist and discovered he is allergic to dust mites, some grass pollens and horse hair (we knew this one). We know we can minimise his symptoms and reactions to these allergens by keeping his diet failsafe, and are considering the de-sensitization path for at least the dust mites – email, Vic.