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Proferrin-ES Side Effects

Generic name: heme iron polypeptide

Note: This document contains side effect information about heme iron polypeptide. Some dosage forms listed on this page may not apply to the brand name Proferrin-ES.

Applies to heme iron polypeptide: oral capsule, oral tablet.


Follow all directions on the product label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

An overdose of this product can be fatal, especially in a young child who has accidentally swallowed it.

Get emergency medical help if you have any of these signs of an allergic reaction while taking heme iron polypeptide (the active ingredient contained in Proferrin-ES) hives, difficulty breathing, swelling of your face, lips, tongue, or throat.

Although not all side effects are known, heme iron polypeptide is thought to be likely safe for most people when used as directed.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

For Healthcare Professionals

Applies to heme iron polypeptide: oral capsule, oral tablet.


Other side effects associated with iron therapy have included iron overload (hemosiderosis).[Ref]

Iron overload (i.e., hemosiderosis) has been reported in patients genetically predisposed, or have underlying disorders, that augment the absorption of iron. It has also occurred following administration of excessive parenteral iron therapy, combination of oral and parenteral iron, or in patients with hemoglobinopathies that were erroneously diagnosed as iron deficiency anemia. Hemosiderosis is treated with repeated phlebotomy or long-term administration of deferoxamine. The liver is particularly susceptible to toxicity in iron-overload states.[Ref]


Gastrointestinal side effects have rarely included queasiness, dark green stool, and Hemoccult-positive stools.[Ref]

Doses of heme iron polypeptide exceeding 56 mg of elemental iron have been reported to cause queasiness and dark green stool.

Patients who receive therapy with heme iron polypeptide and have a positive reaction to an occult stool test may require further work-up.[Ref]


Immunologic side effects associated with iron therapy have rarely included gastroenteritis associated with Yersinia enterocolitica and Listeria monocytogenes in patients with iron overload status receiving treatment with deferoxamine.[Ref]

It has been hypothesized that gastroenteritis is caused by bacteria that become virulent in the presence of iron overload resulting in a systemic infection. Treatment consists of discontinuing deferoxamine and initiating appropriate antimicrobial therapy.[Ref]


1. Product Information. Proferrin-ES (heme iron polypeptide). Colorado Biolabs Inc. 2005.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.