Colon cancer patients can take ferrous sulfate without contraindications of ferrous sulfate, if in the process of treatment, are using other drugs, it is recommended to consult a physician or pharmacist to clarify whether it can be taken. Ferrous sulfate can be used for iron deficiency anemia caused by various reasons such as chronic blood loss, pregnancy, malnutrition, etc. Adverse reactions include nausea, vomiting, constipation, etc. Contraindications include alcoholism, hepatitis, acute infections, intestinal inflammation, pancreatitis, gastroduodenal ulcer, ulcerative colitis. If colon cancer patients do not have the above contraindications, in the case of iron deficiency anemia, they can take ferrous sulfate to supplement iron and correct iron deficiency anemia. If they are in the treatment stage and using other drugs at the same time, it is recommended to consult the physician or pharmacist before taking it.