That's what I'm taking, after taking 100mg 3x a day for a few weeks. Today after my afternoon dose, I felt so dizzy, so I think I need to go back to 100mg in the afternoon. I'm extremely sensitive to meds. Doctors, unfortunately, think I'm fibbing until I get sick , then they take note. I had a horrible bout of UTI lately, took 3 series of antibiotics, I kept telling him I cannot take a certain group of antibiotics but he insisted on it, until I felt worse than my UTI. Now my doctor is listening. Nobody knows our bodies better than ourselves. Take care, I hope you get the answers from your doctor. Keep us posted. Thank you.