Is it normal to feel like crap on flagyl? Do others think it indicates some type of bacterial die off? would someone without any infections would they feel any effects? I dose once a day every so 0ften but 2 or more days in a row and feel like crap, not to different to what I have read on cpn forum or lyme forums. i take bactrim regularly to keep sinusitis away which it has done a good job. I also have thought it may help with some other undiagnosed infections common in cfs. Testing is unreliable and supposedly lyme doesn't exist in australia even though its been proven it does exist with autopsies and blood sent overseas for testing etc Besides sinusitis , I feel better on abx and add other abx every so often but flagyl knocks me around. Is it indicating lyme, cpn or mycoplasma not picked up in testing???