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Ferrous Sulfate

Pronunciation

Pronunciation

(FER us SUL fate)

Index Terms

  • Feosol Original
  • Ferric Sulfate
  • Ferrous Sulphate
  • FeSO4
  • Iron Sulfate
  • Slow FE

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Elixir, Oral:

FeroSul: 220 (44 Fe) MG/5ML (473 mL) [contains alcohol, usp, fd&c yellow #6 (sunset yellow), propylene glycol, saccharin sodium, sodium benzoate; lemon flavor]

Generic: 220 (44 Fe) MG/5ML (5 mL [DSC], 473 mL)

Liquid, Oral:

Generic: 220 (44 Fe) MG/5ML (473 mL)

Solution, Oral:

BProtected Pedia Iron: 75 (15 Fe) MG/ML (50 mL) [alcohol free, gluten free; contains sodium metabisulfite; citrus flavor]

Fer-In-Sol: 75 (15 Fe) MG/ML (50 mL) [contains alcohol, usp, sodium bisulfite]

Fer-Iron: 75 (15 Fe) MG/ML (50 mL) [contains sodium metabisulfite; lemon flavor]

Iron Supplement Childrens: 75 (15 Fe) MG/ML (50 mL) [alcohol free, dye free, gluten free, lactose free; contains sodium bisulfite]

Generic: 75 (15 Fe) MG/ML (50 mL)

Syrup, Oral:

Generic: 300 (60 Fe) MG/5ML (5 mL)

Tablet, Oral:

Ferro-Bob: 325 (65 Fe) MG

Generic: 325 (65 Fe) MG

Tablet, Oral [preservative free]:

FerrouSul: 325 (65 Fe) MG [sodium free, starch free]

Generic: 325 (65 Fe) MG

Tablet Delayed Release, Oral:

Generic: 324 (65 Fe) MG, 325 (65 Fe) MG

Tablet Extended Release, Oral:

Slow Fe: 160 (50 Fe) MG [DSC]

Slow Fe: 142 (45 Fe) MG [contains fd&c blue #1 aluminum lake, fd&c red #40 aluminum lake, fd&c yellow #6 aluminum lake]

Slow Release Iron: 140 (45 Fe) MG [DSC] [contains brilliant blue fcf (fd&c blue #1), fd&c red #40 aluminum lake, fd&c yellow #6 aluminum lake]

Tablet Extended Release, Oral [preservative free]:

Slow Iron: 160 (50 Fe) MG [gluten free]

Generic: 140 (45 Fe) MG

Brand Names: U.S.

  • BProtected Pedia Iron [OTC]
  • Fer-In-Sol [OTC]
  • Fer-Iron [OTC]
  • FeroSul [OTC]
  • Ferro-Bob [OTC]
  • FerrouSul [OTC]
  • Iron Supplement Childrens [OTC]
  • Slow Fe [OTC]
  • Slow Iron [OTC]
  • Slow Release Iron [OTC] [DSC]

Pharmacologic Category

  • Iron Salt

Pharmacology

Replaces iron, found in hemoglobin, myoglobin, and other enzymes; allows the transportation of oxygen via hemoglobin

Absorption

Iron is absorbed in the duodenum and upper jejunum; in persons with normal serum iron stores, 10% of an oral dose is absorbed; this is increased to 20% to 30% in persons with inadequate iron stores. Food and achlorhydria will decrease absorption

Excretion

Urine, sweat, sloughing of the intestinal mucosa, and menses

Onset of Action

Hematologic response: Oral: ~3-10 days

Peak effect: Reticulocytosis: 5-10 days; hemoglobin increases within 2-4 weeks

Protein Binding

To transferrin

Use: Labeled Indications

Prevention and treatment of iron-deficiency anemias

Contraindications

Hypersensitivity to iron salts or any component of the formulation; hemochromatosis, hemolytic anemia

Dosing: Adult

Note: Multiple concentrations of ferrous sulfate oral liquid exist; close attention must be paid to the concentration when ordering and administering ferrous sulfate; incorrect selection or substitution of one ferrous sulfate liquid for another without proper dosage volume adjustment may result in serious over- or underdosing. Dose expressed in terms of elemental iron; ferrous sulfate contains ~20% elemental iron; ferrous sulfate exsiccated (dried) contains ~30% elemental iron:

Dietary Reference Intake: Oral:

19 to 50 years: Males: 8 mg daily; Females: 18 mg daily; Pregnant females: 27 mg daily; Lactating females: 9 mg daily

≥50 years: 8 mg daily

Iron deficiency anemia, prevention: Oral: 60 mg once daily (Stoltzfus, 1998; WHO, 2001).

Iron deficiency anemia, treatment of iron deficiency: Oral: 100 to 200 mg daily in 2 to 3 divided doses (Liu, 2012; Stoltzfus, 1998; WHO, 2001). Note: Extended release tablets are intended for once daily use.

Dosing: Geriatric

Lower doses (15-50 mg elemental iron/day) may have similar efficacy and less GI adverse events (eg, nausea, constipation) as compared to higher doses (eg, 150 mg elemental iron/day) (Rimon 2005).

Dosing: Pediatric

Note: Multiple concentrations of ferrous sulfate oral liquid exist; close attention must be paid to the concentration when ordering and administering ferrous sulfate; incorrect selection or substitution of one ferrous sulfate liquid for another without proper dosage volume adjustment may result in serious over- or underdosing. Dosage expressed in terms of elemental iron; ferrous sulfate contains ~20% elemental iron; ferrous sulfate exsiccated (dried) contains ~30% elemental iron:

Dietary Reference Intake: Oral:

0 to 6 months: 0.27 mg daily (adequate intake)

7 to 12 months: 11 mg daily

1 to 3 years: 7 mg daily

4 to 8 years: 10 mg daily

9 to 13 years: 8 mg daily

14 to 18 years: Males: 11 mg daily; Females: 15 mg daily; Pregnant females: 27 mg daily; Lactating females: 10 mg daily

Iron deficiency anemia, prevention: Oral:

Infants ≥4 months (receiving human milk as only nutritional source or >50% as source of nutrition without iron fortified food): 1 mg/kg/day (Baker, 2010); Note: In healthy, term infants, AAP does not recommend routine additional supplementation of iron be considered until at least 4 to 6 months of age if breast-fed (full or partial) (Baker, 2010; Schanler, 2011).

Infants and Children 6 months to <2 years in areas where anemia prevalence is >40% and iron fortified foods not available: 2 mg/kg/day (WHO, 2001).

Children 2 years to <5 years in areas where anemia prevalence is >40%: 2 mg/kg/day (maximum dose: 30 mg/day) (WHO, 2001)

Children ≥5 years in areas where anemia prevalence is >40%: 30 mg daily with folic acid (WHO, 2001).

Adolescent in areas where anemia prevalence is >40%: 60 mg daily with folic acid (WHO, 2001).

Iron deficiency anemia, treatment of iron deficiency: Oral: 3 to 6 mg/kg/day in 3 divided doses (Carney, 2010, Kliegman, 2011).

Administration

Do not chew or crush extended release preparations; administer with water or juice on an empty stomach; administer 2 hours prior to, or 4 hours after antacids.

Dietary Considerations

Should be taken with water or juice on an empty stomach; may be administered with food to prevent irritation; however, not with cereals, dietary fiber, tea, coffee, eggs, or milk.

Ferrous sulfate contains ≈ 20% elemental iron (ie, 325 mg ferrous sulfate is equivalent to 65 mg elemental iron); ferrous sulfate exsiccated (dried) contains ≈ 30% elemental iron.

Dietary sources of iron include beans, cereal (enriched), clams, beef, lentils, liver, oysters, shrimp, and turkey. Foods that enhance dietary absorption of iron include broccoli, grapefruit, orange juice, peppers and strawberries. Foods that decrease dietary absorption of iron include coffee, dairy products, soy products, spinach, and tea.

Storage

Iron is a leading cause of fatal poisoning in children. Store out of children's reach and in child-resistant containers.

Drug Interactions

Alpha-Lipoic Acid: Iron Salts may decrease the absorption of Alpha-Lipoic Acid. Alpha-Lipoic Acid may decrease the absorption of Iron Salts. Consider therapy modification

Antacids: May decrease the absorption of Iron Salts. Consider therapy modification

Bisphosphonate Derivatives: Iron Salts may decrease the serum concentration of Bisphosphonate Derivatives. Management: Avoid administration of oral iron supplements within: 2 hours before or after tiludronate/clodronate/etidronate; 60 minutes after oral ibandronate; or 30 minutes after alendronate/risedronate. Exceptions: Pamidronate; Zoledronic Acid. Consider therapy modification

Cefdinir: Iron Salts may decrease the serum concentration of Cefdinir. Red-appearing, non-bloody stools may also develop due to the formation of an insoluble iron-cefdinir complex. Management: Avoid concurrent cefdinir and oral iron when possible. Separating doses by several hours may minimize interaction. Iron-containing infant formulas do not appear to interact with cefdinir. Consider therapy modification

Deferiprone: Iron Salts may decrease the serum concentration of Deferiprone. Management: Separate administration of deferiprone and oral medications or supplements that contain polyvalent cations by at least 4 hours. Consider therapy modification

Dimercaprol: May enhance the nephrotoxic effect of Iron Salts. Avoid combination

Dolutegravir: Iron Salts may decrease the serum concentration of Dolutegravir. Management: Administer dolutegravir at least 2 hours before or 6 hours after oral iron. Alternatively, dolutegravir and oral iron can be taken together with food. Consider therapy modification

Eltrombopag: Iron Salts may decrease the serum concentration of Eltrombopag. Management: Administer eltrombopag at least 2 hours before or 4 hours after oral administration of any iron-containing product. Consider therapy modification

Ferric Hydroxide Polymaltose Complex: May decrease the serum concentration of Iron Salts. Specifically, the absorption of oral iron salts may be reduced. Management: Do not administer intravenous (IV) ferric hydroxide polymaltose complex with other oral iron salts. Therapy with oral iron salts should begin 1 week after the last dose of IV ferric hydroxide polymaltose complex. Consider therapy modification

H2-Antagonists: May decrease the absorption of Iron Salts. Monitor therapy

Levodopa: Iron Salts may decrease the serum concentration of Levodopa. Only applies to oral iron preparations. Management: Consider separating doses of the agents by 2 or more hours to minimize the effects of this interaction. Monitor for decreased therapeutic effects of levodopa during concomitant therapy, particularly if doses cannot be separated. Consider therapy modification

Levothyroxine: Iron Salts may decrease the serum concentration of Levothyroxine. Management: Separate oral administration of iron salts and levothyroxine by at least 4 hours. Separation of doses is not required with parenterally administered iron salts or levothyroxine. Consider therapy modification

Methyldopa: Iron Salts may decrease the serum concentration of Methyldopa. Consider therapy modification

Pancrelipase: May decrease the absorption of Iron Salts. Monitor therapy

PenicillAMINE: Iron Salts may decrease the absorption of PenicillAMINE. Only oral iron salts are a concern. Consider therapy modification

Phosphate Supplements: Iron Salts may decrease the absorption of Phosphate Supplements. Management: This applies only to oral phosphate and iron administration. Administer oral phosphate supplements at least 1 hour before, or 2 hours after, oral iron salt administration. Exceptions: Sodium Glycerophosphate Pentahydrate. Consider therapy modification

Proton Pump Inhibitors: May decrease the absorption of Iron Salts. Monitor therapy

Quinolone Antibiotics: Iron Salts may decrease the serum concentration of Quinolone Antibiotics. Management: Administer oral quinolones at least several hours before (4 h for moxi- and sparfloxacin, 2 h for others) or after (8 h for moxi-, 6 h for cipro-, 4 h for lome-, 3 h for gemi-, and 2 h for levo-, nor-, or ofloxacin or nalidixic acid) oral iron salts. Exceptions: LevoFLOXacin (Oral Inhalation). Consider therapy modification

Tetracycline Derivatives: May decrease the absorption of Iron Salts. Iron Salts may decrease the serum concentration of Tetracycline Derivatives. Consider therapy modification

Trientine: May decrease the serum concentration of Iron Salts. Iron Salts may decrease the serum concentration of Trientine. Management: Trientine manufacturer recommends avoiding concurrent use with oral iron salts due to the risk for impaired GI absorption of both trientine and the iron salt. Short courses of iron may be used; however, separate administration by at least 2 hours. Consider therapy modification

Test Interactions

False-positive for blood in stool by the guaiac test

Adverse Reactions

Frequency not defined.

>10%: Gastrointestinal: Constipation, darkening of stools, epigastric pain, gastrointestinal irritation, nausea, stomach cramps, vomiting

1% to 10%:

Gastrointestinal: Dental discoloration (temporary; liquid preparations), diarrhea, heartburn

Genitourinary: Urine discoloration

<1% (Limited to important or life-threatening): Contact dermatitis

Warnings/Precautions

Disease-related concerns:

• Gastrointestinal disease: Avoid in patients with peptic ulcer, enteritis, or ulcerative colitis.

Special populations:

• Blood transfusion recipients: Avoid in patients receiving frequent blood transfusions.

• Elderly: Anemia in the elderly is often caused by “anemia of chronic disease” or associated with inflammation rather than blood loss. Iron stores are usually normal or increased, with a serum ferritin >50 ng/mL and a decreased total iron binding capacity. Hence, the “anemia of chronic disease” is not secondary to iron deficiency but the inability of the reticuloendothelial system to reclaim available iron stores.

• Pediatric: Accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under 6 years of age. Keep this product out of the reach of children. In case of accidental overdose call the poison control center immediately.

• Premature infants: Avoid use in premature infants until the vitamin E stores, deficient at birth, are replenished.

Dosage form specific issues:

• Polysorbate 80: Some dosage forms may contain polysorbate 80 (also known as Tweens). Hypersensitivity reactions, usually a delayed reaction, have been reported following exposure to pharmaceutical products containing polysorbate 80 in certain individuals (Isaksson 2002; Lucente 2000; Shelley 1995). Thrombocytopenia, ascites, pulmonary deterioration, and renal and hepatic failure have been reported in premature neonates after receiving parenteral products containing polysorbate 80 (Alade 1986; CDC 1984). See manufacturer’s labeling.

• Propylene glycol: Some dosage forms may contain propylene glycol; large amounts are potentially toxic and have been associated hyperosmolality, lactic acidosis, seizures, and respiratory depression; use caution (AAP 1997; Zar 2007).

Other warnings/precautions:

• Duration of therapy: Administration of iron for >6 months should be avoided except in patients with continuous bleeding or menorrhagia.

Monitoring Parameters

Serum iron, total iron binding capacity, reticulocyte count, hemoglobin

Pregnancy Considerations

Iron crosses the placenta and fetal stores are obtained from the mother (McArdle 2011). Iron requirements are increased in pregnant women compared to nonpregnant females (IOM 2001). All pregnant women should be tested for iron deficiency anemia and treated with supplemental iron if needed (ACOG 2008; CDC 1998). Untreated iron deficiency anemia during pregnancy may be associated with an increased risk of low birth weight, preterm delivery, and perinatal mortality, as well as postpartum depression in the mother and decreased mental functioning in the offspring (ACOG 2008; CDC 1998; IOM 2001). Treatment improves maternal hematologic status and neonatal birth weight (Haider 2013).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience diarrhea; constipation; stool discoloration; lack of appetite; abdominal cramps; or staining of mouth, teeth, or fillings. Have patient report immediately to prescriber melena, severe nausea, significant dyspepsia, or hematemesis (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.

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