I just started Colisting on Friday (June 4). I used to take Tobi but it caused so much upper airway inflammation and bad laryngitis that I had to go off of it. Also, my bugs were resistant to Tobra but not to Colistin.Well - the Colistin immediately started making me wheeze and feel really tight and irritated. My peak flow dropped drastically (from 370 to 290) and I felt very short of breath. That afternoon, I got out a few very productive coughs and felt ok for awhile, then shortly before my evening treatment, felt bad again. However that night - my peak flow went up to 380 - the highest that it's been in a year.Saturday had the same problem - had a lot of trouble walking around. But that night - I got out more crap from my lungs then I have ever seen. I felt amazing for about 2 hours, but then everything tightened up again. Peak flow was 330.Sunday - the side effects weren't quite as bad, but I got really short of breath during the evening. Peak flow was only 300.Today - I still wheezed while taking the meds but wasn't quite as tight the rest of the day. I look like crap though - big dark circles under my eyes like I'm not feeing well, and I don't feel great. My cough on the Colistin is very different - I get all rattly and the coughs suddenly "pop" out and my sputum looks very different - some of it is white - I've never had white and my parents said that is new sputum that is just starting to get infected - so it's a good thing.Anyway - I'm just wondering if the side effects go away and the wheezing and tightness stop. My assumption is that I feel like crap because it's actually going in there and killing the bugs which is causing my airways to block up as the stuff moves out. My docs haven't said much to help other than keep with it if I want to. What are you experiences with it?Thank you!Piper