|
THE INFORMATION IN THE OBPHARMACOPOEIATM
IS INTENDED SOLELY FOR USE BY THE MEDICAL PROFESSION. IT IS NOT INTENDED FOR LAY PERSONS.
FOCUS INFORMATION TECHNOLOGY, INC. DOES NOT ASSUME ANY RESPONSIBILITY FOR ANY ASPECT OF
HEALTHCARE ADMINISTERED WITH THE AID OF THIS CONTENT. THE PRESCRIBING PHYSICIAN
MUST BE FAMILIAR WITH THE FULL PRODUCT LABELING AS PROVIDED BY THE MANUFACTURER AND RELEVANT MEDICAL LITERATURE PRIOR TO USING THE OBPHARMACOPOEIATM
.
Oral Iron Therapy
|
Accidental overdose of iron-containing products is a leading cause of fatal
poisoning in children younger than 6 years.
US national poison hotline at 1-800-222-1222
Web Site: www.poison.org
|
The Centers for Disease Control (CDC) recommends low-dose iron supplementation (30 mg/d) from the first prenatal visit and
encouraging iron-rich foods [4]. However, taking iron before 20 weeks can worsen the nausea and vomiting of pregnancy in some women.
Ferrous sulfate (Feosol,Fer-In-Sol ® Syrup)
Available over the counter (OTC)
- Treatment of low blood levels of iron.
325 mg orally three times daily between meals separately from other medications
OR
10 mL syrup orally three times daily between meals
separately from other medications.
An increase in the hemoglobin concentration of at least 2 g/dL after 3 weeks of
therapy generally is used as the criterion for an adequate therapeutic response
[5]
Contraindicated in: Hemosiderosis, hemochromatosis, and
hemolytic anemia.
Ferrous sulfate reduces absorption of levothyroxine and methyldopa [6,7]
Gastrointestinal side effects including nausea, constipation, diarrhea and
abdominal pain are dose related.Docusate 100 mg bid may be given to reduce constipation.
(325 mg (65 mg elemental iron) tablets, 150 mg (30 mg elemental iron)per 5 mL syrup -250 mL bottle)
Carbonyl Iron (Feosol Caplet). Available over the counter (OTC)
This form of iron may be less toxic than iron salts. However
bioavailability is about 70% of ferrous sulfate [8-11].
- Treatment of low blood levels of iron .
45 mg orally three to four times daily between meals separately from other medications
An increase in the hemoglobin concentration of at least 2 g/dL after 3 weeks of
therapy generally is used as the criterion for an adequate therapeutic response
[5]
Contraindicated in: Hemosiderosis, hemochromatosis, and
hemolytic anemia.
Ferrous sulfate reduces absorption of levothyroxine and methyldopa [6,7].
Gastrointestinal side effects including nausea, constipation, diarrhea and
abdominal pain are dose related. Docusate 100 mg bid may be given to reduce constipation.
(45 mg (45 mg elemental iron) caplets )
Parenteral Iron Therapy
Indications for the use of intravenous iron include intestinal malabsorption, intolerance to oral iron, nonadherence,
or a hemoglobin level less than 6 g per dL (60 g per L) with signs of poor
perfusion in patients who would otherwise receive transfusion (e.g., those who
have religious objections) [12,13]. Consider evaluating for celiac disease in
patients refractory to oral iron therapy [14,15].
The iron dose to give may be calculated from the following formula [16,
17] :
Total iron deficit [mg] =
body weight [kg] x (target Hb-actual Hb) [g/dl] x 2.4* + depot iron [mg]
* 2.4 is a factor that takes into account the patient's blood volume, hemoglobin iron content , and conversion from g/dL to mg/L . 2.4 =
0.07 x 0.0034 x 10000:
Where:
Blood volume: ~7% of body weight
Iron content of haemoglobin ~0.34%
Conversion from g/dl to mg/l =10000
Depot iron =500 mg. Depot iron refers to the approximately 20% of the total iron content in the
body stored in ferritin and hemosiderin in cells of the recticuloendothelial
system (liver, spleen, and bone marrow).
Pre-medications
Patients with a history of infusion reaction may be given
medications to help reduce the likelihood of a recurrent reaction.
-
Acetaminophen 650 mg PO 15-30 minutes pre-infusion AND
-
Diphenhydramine 25 mg IV push 15-30 minutes pre-infusion OR
-
Diphenhydramine 25 mg PO 15-30 minutes pre-infusion
For anaphylactic reactions (hives, flushing, wheezing, shortness of
breath, chest pain, tachycardia hypotension, etc) see
Initial Treament
of Anaphylactic Reaction
Iron Sucrose Injection (Venofer® )
- Treatment of low blood levels of iron in patients with chronic kidney
disease, intestinal malabsorption, or intolerance to oral iron.
100 mg vial undiluted by slow intravenous injection over 5 minutes
(20 mg/minute) one to three times per week
OR
200 mg vial undiluted by slow intravenous injection over 10 minutes(20 mg/minute) one to three
times per week [16]
OR
200 mg diluted in 100 mL normal saline given as a slow
intravenous infusion administered over 30 minutes one to three times per week [17].
Contraindications: Known hypersensitivity to iron sucrose , evidence of iron overload (ferritin > 800 ng/mL and/or TSAT > 50%), or evidence of severe infection (such as sepsis or osteomyelitis)
(Each 5 mL vial contains 100 mg elemental iron (20 mg/mL) and each 10 mL vial contains 200 mg elemental iron (20 mg/mL))
REFERENCES
1. Carles G, Tobal N, Raynal P, Herault S, Beucher G, Marret H, et al.
Doppler assessment of the fetal cerebral hemodynamic response to moderate or
severe maternal anemia. Am J Obstet Gynecol 2003;188:794–9.
2. Sifakis S, Pharmakides G. Anemia in pregnancy. Ann N Y Acad Sci
2000;900:125–36.
3.ACOG Practice Bulletin No. 95: anemia in pregnancy.Obstet Gynecol
2008;112(1):201-7.PMID: 18591330
4. Recommendations to prevent and control iron deficiency in the United
States. Centers for Disease Control and Prevention. MMWR Recomm Rep
1998;47(RR-3):1–29.
5.Brittenham GM.Disorders of iron metabolism: iron deficiency and
overload.In: Hoffman R, Benz EJ Jr, Skikne B, et al, eds. Hematology: Basic
Principles and Practice. 4th ed. New York, NY: Churchill Livingstone;
2004:481-487.
6.Campbell NR et al. Ferrous sulfate reduces methyldopa absorption:
methyldopa: iron complex formation as a likely mechanism.
Clin Invest Med. 1990 Dec;13(6):329-32.PMID: 2078911
7. Alteration of methyldopa absorption, metabolism, and blood pressure
control caused by ferrous sulfate and ferrous gluconate.Clin Pharmacol Ther. 1988 Apr;43(4):381-6.PMID: 3356082
8. Gordeuk VR et al., High-dose carbonyl iron for iron deficiency anemia: a
randomized double-blind trial.Am J Clin Nutr. 1987 Dec;46(6):1029-34.
PMID: 3318377
9. Devasthali SD et al., Bioavailability of carbonyl iron: a randomized,
double-blind study.Eur J Haematol. 1991 May;46(5):272-8.PMID: 2044721
10.Gordeuk VR, Brittenham GM, McLaren CE, Hughes MA, Keating LJ. Carbonyl
iron therapy for iron deficiency anemia. Blood 1986 Mar;67(3):745-752.
11. Brittenham GM, Klein HG, Kushner JP, Ajioka RS. Preserving the national
blood supply. Hematology Am Soc Hematol Educ Program. 2001:422-32.
12. Hamstra RD, Block MH, Schocket AL. Intravenous iron dextran in clinical
medicine. JAMA 1980;243:1726–31.
13. Hallak M, et al. Supplementing iron intravenously in pregnancy. A way to
avoid blood transfusions.J Reprod Med. 1997 Feb;42(2):99-103. PMID: 9058345
14. Pemmaraju N. An Absorbing Problem Am J Med. 2007 Mar;120(3):229-30.
PMID: 17349442
15 Ransford R.A. J., Hayes M., Palmer M., Hall M.J.: J Clin
Gastroenterol 35. (3): 228-233.2002
16. Bayoumeu F, Subiran-Buisset C, Baka NE, Legagneur H, Monnier- Barbarino
P, Laxenaire MC. Iron therapy in iron deficiency anemia in pregnancy:
intravenous route versus oral route. Am J Obstet Gynecol. 2002
Mar;186(3):518-22. PMID: 11904617
17. RA Al , et al., Intravenous versus oral iron for treatment of anemia in pregnancy: a randomized trial.Obstet Gynecol. 2005 ;106(6):1335-40. PMID: 16319260
18. Venofer® (Iron Sucrose Injection, USP) package insert. American Regent, Inc. Shirley, NY, 11967
|
