Pregnant taking ferrous sulfate 325 mg twice daily is 6 hrs long enough to wait before taking another dose? how close is to close for doses?

Iron supplements: Taking iron more frequently won't cause any problem other than complication. The body will only absorb a certain amount and the remainder will pass through your system. The most common complaint with excess iron is constipation. Therefore, you can take it at 6 hour intervals if you don't have symptoms now but you may have symptoms as your body reaches its capacity to absorb the iron.

Ferrous sulfate: If you are taking it twice daily, then take it every 12 hours if you can. I think every 6 hours is ok too if you don't have too much stomach upset.