A nurse is teaching a client who has iron deficiency anemia about ferrous sulfate. Which of the following instructions should the nurse include in the teaching?

A. Taking iron at bedtime may reduce adherence because gastrointestinal side effects such as nausea, stomach cramps, or constipation can interfere with sleep. Therefore, it’s not the preferred timing. B. Antacids contain magnesium or calcium, which bind to iron and significantly reduce its absorption, decreasing the effectiveness of the treatment. C. Iron is absorbed most efficiently on an empty stomach because food, especially dairy or high-fiber products, can impair absorption. Ideally, it should be taken 1 hour before or 2 hours after meals, and vitamin C or citrus juice can be taken with it to enhance absorption. D. Dairy products contain calcium, which competes with iron for absorption in the gut. Taking iron with yogurt can reduce its bioavailability and delay correction of anemia.