I nebulize colistimethate every other month every other day during that month. On the days I'm not nebulizing I take cipro 250mg. My ID doc took this route since I'm so prone to becoming antibiotic resistant. At first I was nebulizing 1.5 ml of colistimethate but that seemed to bother me. That was reduced to 1 ml (which is just a couple of deep breaths) and I seem to be OK with that. Take care my SOB friends!!!