Yes, you can safely take iron and vitamin D supplements together, as they do not interfere with each other. For optimal absorption, take your iron supplement on an empty stomach (or with vitamin C), and your vitamin D with a meal. Typically, vitamin D deficiency is treated with weekly high-dose cholecalciferol for 8 weeks, followed by daily maintenance. Iron deficiency is managed with daily oral iron (like ferrous sulfate) for 3 to 6 months to replenish stores. Your doctor will monitor your progress with routine blood tests to ensure your levels return to normal safely.