Side Effects of Ferrous Sulfate

Updated November 21, 2016

Ferrous sulphate is used for the treatment of iron deficiency anaemia. Anemia results in fatigue and shortness of breath. Ferrous sulphate replaces iron necessary for the health of your red blood cells. It is available in capsules, drops and elixir, and should be taken as directed by your physician. Ferrous sulphate does have some side effects.


Ferrous sulphate can result in nausea, stomach upset or stomach pain. Taking it with food or milk can help alleviate these symptoms.


Ferrous sulphate can cause your stools to be darker than normal or green in colour. In addition, it can result in constipation. Increased fluid intake, especially water, can help relieve constipation.

Stained Teeth

Using liquid forms of ferrous sulphate can result in stained teeth. To prevent this, you should take the liquid form mixed in juice or water and sip it through a straw.

Iron Overload

According to, iron overload, or hemosiderosis, can occur following excessive iron therapy or in cases where iron deficiency anaemia was misdiagnosed. This condition is treated with deferoxamine.

Drug Interactions

Ferrous sulphate may result in an adverse reaction when taken with antacids, alendronate, chloramphenicol, cefdinir, deferoxamine, cholestyramine, etidronate, dimercaprol, pancreatic enzymes, risedronate, tetracycline and some other antibiotics, thyroid hormones and medications for stomach ulcers or other stomach conditions.


Before taking ferrous sulphate, inform your doctor if you have bowel disease, hemolytic anaemia, liver disease, iron overload or stomach ulcer, or if you are pregnant, breast-feeding, frequently drink alcohol or have had an allergic reaction to iron or other medications.

Cite this Article A tool to create a citation to reference this article Cite this Article

About the Author