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Iron Preparations, Oral

Class: Iron Preparations
CAS Number: 1332-96-3
Brands: Feosol, Feostat, Feratab, Fer-Gen-Sol, Fergon, Fer-In-Sol, Ferrex, Ferrous Sulfate Tablets EC, Fe-Tinic, Hemocyte, Hytinic, Icar Pediatric, Ircon, Mol-Iron, Nephro-Fer, Niferex, Slow FE

Introduction

Ferrous fumarate, ferrous gluconate, ferrous sulfate, carbonyl iron, and polysaccharide-iron complex are used orally in the prevention and treatment of iron deficiency.

Uses for Iron Preparations, Oral

Prevention and Treatment of Iron Deficiency

Prevention and treatment of iron deficiency. Not indicated for treatment of anemia resulting from causes other than iron deficiency.

Iron Preparations, Oral Dosage and Administration

Administration

Oral Administration

Administer orally between meals (e.g., 1 hour before or 2 hours after a meal).

For patients who have difficulty tolerating oral iron supplements, administer smaller, more frequent doses; start with a lower dose and increase slowly to the target dose; try a different form or preparation; or take with or after meals or at bedtime.

Dosage

Dosage expressed in terms of elemental iron. (See Table 1.)

Do not exceed recommended dosage.

Carbonyl iron is elemental iron, not an iron salt.

Table 1. Approximate Elemental Iron Content of Various Oral Iron Preparationsa

Drug

Elemental Iron

Ferric pyrophosphate

120 mg/g

Ferrous gluconate

120 mg/g

Ferrous sulfate

200 mg/g

Ferrous sulfate, dried

300 mg/g

Ferrous fumarate

330 mg/g

Ferrous carbonate, anhydrous

480 mg/g

Carbonyl iron

1000 mg/g

Pediatric Patients

Iron Deficiency Anemia
Prevention
Oral

Premature or low-birthweight infants: 2–4 mg/kg daily starting preferably at 1 month, but at least by 2 months, of age. Do not exceed 15 mg daily.

Normal full-term infants who are not breast-fed or are only partially breast-fed: 1 mg/kg daily, preferably as iron-fortified formula, starting at birth and continuing during the first year of life. Do not exceed 15 mg daily.

Children ≥10 years of age who have begun their pubertal growth spurt may require daily iron supplementation of 2 or 5 mg daily in males or females, respectively.

Based on the need to maintain a normal functional iron concentration but only minimal stores, RDA is the goal for dietary intake in individuals.

Established for infants through 6 months of age based on the observed mean iron intake of infants fed principally human milk.

Table 2. Recommended Dietary Allowance (RDA)/Adequate Intake (AI) of Iron for Pediatric Patients188

Age

RDA (mg/day)

AI (mg/day)

Infants 0–6 months of age

0.27

Infants 7–12 months of age

11

Children 1–3 years of age

7

Children 4–8 years of age

10

Children 9–13 years of age

8

Children 14–18 years of age

Boys: 11

Girls: 15

Treatment
Oral

Children: 3–6 mg/kg daily in 3 divided doses.

If a satisfactory response is not noted after 3 weeks of oral iron therapy, consideration should be given to the possibilities of patient noncompliance, simultaneous blood loss, additional complicating factors, or incorrect diagnosis.

Adults

Iron Deficiency Anemia
Prevention
Oral

RDA for healthy men of all ages (≥19 years of age) is 8 mg daily.

RDA for healthy women 19–50 years of age is 18 mg daily, and RDA for healthy women ≥51 years of age is 8 mg daily.

Treatment
Oral

Usual therapeutic dosage: 50–100 mg 3 times daily. Smaller dosages (e.g., 60–120 mg daily) also recommended if patients are intolerant of oral iron, but the possibility that iron stores will be replenished at a slower rate should be considered.

If a satisfactory response is not noted after 3 weeks of oral iron therapy, consider possibility of patient noncompliance, simultaneous blood loss, additional complicating factors, or incorrect diagnosis.

Normal hemoglobin values usually obtained in 2 months unless blood loss continues. In severe deficiencies, continue iron therapy for approximately 6 months.

Special Populations

Renal Impairment

Iron Deficiency Anemia
Anemia of Chronic Renal Failure in Hemodialysis Patients Receiving Epoetin Alfa
Oral

Children: 2–3 mg/kg daily in 2 or 3 divided doses.

Adults: ≥200 mg daily in 2 or 3 divided doses.

Pregnant Women

RDA for pregnant women 14–50 years of age is 27 mg daily.

Lactating Women

RDA for lactating women 14–18 or 19–50 years of age is 10 or 9 mg daily, respectively.

Cautions for Iron Preparations, Oral

Contraindications

  • Primary hemochromatosis.

  • Peptic ulcer, regional enteritis, or ulcerative colitis.

Warnings/Precautions

Warnings

Children <12 years of age and pregnant or nursing women should consult a health professional before using iron-containing preparations.

Accidental Overdose

Possible fatal poisoning in children <6 years of age; keep iron-containing preparations out of reach of children.

If accidental overdosage occurs, immediately contact a clinician or a poison control center.

Sensitivity Reactions

Allergic Reactions

Possible allergic reactions (e.g., bronchial asthma) with Fergon 225-mg tablets, which contain the dye tartrazine (FD&C yellow No. 5). Use with caution, particularly in patients sensitive to aspirin.

Major Toxicities

Excess Iron Stores

Excess storage of iron with secondary hemochromatosis possible; not recommended for treatment of hemolytic anemias (unless an iron-deficient state also exists) or for patients receiving repeated blood transfusions.

Do not administer for >6 months except in patients with continued bleeding, menorrhagia, or repeated pregnancies.

General Precautions

Infectious Complications

Possible increased pathogenicity of certain microorganisms, including possible adverse effects on prognosis in HIV-infected individuals; not recommended for use in individuals without documented iron deficiency.

Use of Fixed Combination

When used in fixed combination with other agents, consider the cautions, precautions, and contraindications associated with the concomitant agents.

Specific Populations

Lactation

Distributed into milk.

Common Adverse Effects

Constipation, diarrhea, dark stools, nausea, epigastric pain.

Interactions for Iron Preparations, Oral

Specific Drugs, Foods, and Laboratory Tests

Drug, Food, or Test

Interaction

Comment

Antacids or aluminum-containing phosphate binders

May decrease iron absorption

Administer these drugs as far apart as possible

Calcium supplements

Pharmacokinetic (decrease iron absorption) interaction

Administer at least 2 hours apart

Chloramphenicol

Possible delayed response to iron therapy

Avoid concomitant use

Food

Iron absorption may be inhibited by polyphenols (e.g., from certain vegetables), tannins (e.g., from tea), phytates (e.g., from bran), and calcium (e.g., from dairy products)

Administer 1 hour before or 2 hours after a meal

H2-receptor antagonists

Increased gastric pH and possibly decreased GI absorption of oral iron preparations that depend on gastric acidity for dissolution and absorption

Administer oral iron at least 1 hour prior to H2-receptor antagonists

Iron, parenteral

Iron toxicity

Concomitant use not recommended

Methyldopa

Pharmacokinetic (decreased oral absorption of methyldopa) and pharmacologic (decreased hypotensive effect) interactions

Monitor BP

Penicillamine

May decrease the cupruretic effect of penicillamine, probably by decreasing its absorption

Administer at least 2 hours apart

Quinolone anti-infectives

Pharmacokinetic interaction (iron may interfere with quinolone absorption)

Administer at least 2 hours apart

Tests for detection of occult blood in stools

Possible false-positive results with guaiac test

Use a benzidine test instead

Tetracyclines

Pharmacokinetic interaction (decreased oral absorption of both iron and tetracyclines)

Administer tetracycline 3 hours after or 2 hours before oral iron

Thyroid agents

Possible pharmacokinetic interaction (decreased thyroxine absorption)

Administer at least 2 hours apart and monitor thyroid function

Vitamin C

Increased absorption of iron from GI tract (with >200 mg Vitamin C per 30 mg elemental iron)

Concomitant use may be of benefit, particularly in infants

Iron Preparations, Oral Pharmacokinetics

Absorption

Bioavailability

Absorption dependent upon the form of iron administered (e.g., ferrous form more readily absorbed), the dose, degree of erythropoiesis, diet, and iron stores. GI absorption of iron increases in iron-deficient individuals.

Oral bioavailability of iron can vary from <1% to >50%, and the principal factor controlling GI iron absorption is the amount of iron stored in the body.

Onset

Symptoms of anemia usually improve within a few days; normal hemoglobin values usually attained in 2 months unless blood loss continues.

Food

Food decreases absorption of inorganic iron. (See Food under Interactions.)

Distribution

Extent

Exists in humans almost exclusively complexed to protein or in heme molecules.

Crosses the placenta and distributes into milk.

Elimination

Metabolism

Occurs in a virtually closed system.

Elimination Route

Most iron liberated by destruction of hemoglobin is conserved and reused by the body. Blood loss greatly increases iron loss.

Stability

Storage

Oral

Capsules, Solutions, Suspensions, Tablets

Room temperature (15–30°C). Protect from excessive heat and moisture.

Actions

  • Corrects erythropoietic abnormalities caused by a deficiency of iron.

  • Does not stimulate erythropoiesis, nor does it correct hemoglobin disturbances not caused by iron deficiency.

Advice to Patients

  • Risk of fatal poisoning in children <6 years of age; importance of keeping iron-containing products out of reach of children.

  • Importance of women informing their clinicians if they are or plan to become pregnant or plan to breast-feed.

  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses.

  • Importance of informing patients of other important precautionary information. (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Carbonyl Iron

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Suspension

15 mg (of iron) per 1.25 mL

Icar Pediatric

Hawthorn

Tablets

45 mg (of iron)

Feosol Caplets

GlaxoSmithKline

Tablets, chewable

15 mg (of iron)

Icar Pediatric

Hawthorn

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Ferrous Fumarate

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Tablets

200 mg (66 mg iron)

Ircon

Kenwood

324 mg (106 mg iron)*

Hemocyte

US Pharmaceutical

325 mg (107 mg iron)*

Ferrous Fumarate Tablets

CMC

350 mg (115 mg iron)

Nephro-Fer

R&D Labs

Tablets, chewable

100 mg (33 mg iron)

Feostat

Forest

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Ferrous Fumarate Combinations

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Capsules, extended-release

150 mg (50 mg iron) with Docusate Sodium 100 mg*

Ferrous Fumarate with DSS Timed Capsules

Vita-Rx

Tablets, extended-release, film-coated

150 mg (50 mg iron) with Docusate Sodium 100 mg

Ferro-DSS Caplets

Time-Caps

Ferro-Sequels (with povidone)

Inverness

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Ferrous Gluconate

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Bulk

Powder

Oral

Tablets

225 mg (27 mg iron)

Fergon (with tartrazine)

Bayer

Ferrous Gluconate Tablets

IVAX, United Research

300 mg (35 mg iron)

Ferrous Gluconate Tablets

Upsher-Smith

320 mg (37 mg iron)*

325 mg (38 mg iron)*

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Ferrous Sulfate

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Bulk

Powder

Oral

Solution

220 mg (44 mg iron) per 5 mL*

Ferrous Sulfate Elixir

Alpharma, IVAX, United Research

300 mg (60 mg iron) per 5 mL

Ferrous Sulfate Solution

Pharmaceutical Associates

125 mg (25 mg iron) per mL*

Fer-Gen-Sol Drops

IVAX

Fer-In-Sol Drops (with alcohol 0.02%)

Mead Johnson

Tablets

195 mg (39 mg iron)*

Mol-Iron (with butylparaben and povidone)

Schering-Plough

300 mg (60 mg iron)*

Feratab

Upsher-Smith

325 mg (65 mg iron)*

Tablets, enteric-coated

325 mg (65 mg iron)*

Ferrous Sulfate Tablets EC

IVAX, Paddock

Tablets, film-coated

325 mg (65 mg iron)

Ferrous Sulfate Tablets

United Research

Ferrous Sulfate, Dried

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Capsules

190 mg (60 mg iron)

Tablets

200 mg (65 mg iron)

Feosol

GlaxoSmithKline

Tablets, extended-release

160 mg (50 mg iron)

Slow FE

Novartis

Polysaccharide-iron Complex

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Capsules

150 mg (of iron)

Ferrex-150

Breckenridge

Fe-Tinic 150

Ethex

Hytinic

Hyrex

Niferex-150 (with benzyl alcohol and parabens)

Ther-Rx

Solution

100 mg (of iron) per 5 mL

Niferex Elixir (with alcohol 10%)

Ther-Rx

Tablets, film-coated

50 mg (of iron)

Niferex

Ther-Rx

Oral iron preparations are also commercially available in combination with vitamins and minerals and oral contraceptives.

AHFS DI Essentials™. © Copyright 2021, Selected Revisions October 23, 2017. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

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