Iron supplements typically take effect after two months of consistent doses. Supplements should be taken for six to 12 months to rebuild the body's iron reserves following a deficiency, according to MedlinePlus.
According to New York Times Health, doctors advise against iron supplements for anyone who eats a healthy diet and shows no sign of anemia. However, for some, iron supplements in tablet form are recommended. Doctors may recommend one to two pills per day based on the severity of the condition. A patient should follow all directives from their physician on iron dosage. Taking more than a recommended dosage will not accelerate iron replenishment and may cause harm because of the side effects of iron tablets.