Rick - when I was on Rifampin, my ID doc told me to take all of it at bedtime because you are right, dividing the dose makes life with MAC even more complicated. Maybe check with your doc via a message?
Sue

Before I take rifampin I checked Google ,the instruction was: Rifampin comes as a capsule to take by mouth. Rifampin works best on an empty stomach; take it 1 hour before or at least 2 hours after a meal. If you have difficulty swallowing the capsule, you may empty its contents into applesauce or jelly. Take rifampin exactly as directed.
What I understand from this instruction is taken the medication with empty stomach (at least 2 hours empty). After taking this medicine at least one hour not to eat.

I take all day dosage rifampin and ethambutol together when I get up at 7am.with a glass of water and empty stomach.after an hour I take morning clarithromycin.with my breakfast. I eat as much as I can . I have avoided continuing losing weight ,although hard to gaining weight.

Yes You are right.
My doctor told me to take Rifampin and clorafazamine with my evening meal, because I go to bed soon after that, so the side effects don’t affect me as strongly.
Otherwise I would have nausea all day long .