Iron is used to treat patients with iron deficiency anemia. During taking iron, it is important to note that iron can cause gastrointestinal reactions, so when taking iron, it is recommended to take it during or after meals to reduce the stimulation of the gastrointestinal tract. It is not recommended to take iron in patients with gastric ulcers, duodenal ulcers, or ulcerative enteritis while taking iron. Iron must be taken in moderation, and the blood routine and serum iron level should be reviewed regularly during the taking period. If the blood routine is normalized after sufficient iron supplementation, or if the serum iron is normalized, you can consider stop taking it. It is also important to pay attention to any allergies while taking iron supplements, but iron allergies are rare, and iron supplements should be used with caution if you have pancreatitis or enteritis.