Ferrous sulfate is used to treat iron-deficiency anemia. Side effects of therapy may include nausea and epigastric abdominal discomfort after taking iron. These side effects may be minimized by taking ferrous sulfate at bedtime. Copperas was given indiscriminately by untrained persons to slaves in the 18th and 19th centuries for various ailments. The knowledge that it would cause violent nausea and vomiting made it an ideal "remedy" for virtually anything that ailed a slave and kept him from work. Many slaves were poisoned and died from this practice.[citation needed]
Ferrous sulfate is also used to fortify various foods with iron, for example, the enriched corn meal in Cheetos