Ferrous Sulfate

　　Ferrous sulfate is used to fortify foods and to treat iron-deficiency anemia. Constipation is a frequent and uncomfortable side effect associated with the administration of oral iron supplements. Stool softeners often are prescribed to prevent constipation. Ferrous sulfate can also be used to stain concrete and some limestones and sandstones a yellowish rust color. Woodworkers use ferrous sulfate solutions to color maple wood a silvery hue.