Your dosage for Riba is 8 am, no anatacids or laxatives until after 10 am, or taken prior to 6 am. Grapefruits and grapefruit
juice is a no-no on treatment. Also, vitamins w/calcium and/or fiber supplements need to be taken outside of the 2 hr window as well. At least this is what I've been told by my doctors. I think it's because it can affect the absorption of the meds.