View source for Chemistry:Iron polymaltose

{{Short description|Iron-based medication}}
'''Iron(III)-hydroxide polymaltose complex'''  is a medication used to treat iron deficiency / iron deficiency anemia and belongs to the group of oral [[Medicine:Iron supplement|iron preparations]]. The preparation is a macromolecular complex, consisting of iron(III) hydroxide (trivalent iron, Fe<sup>3+</sup>, Fe(OH)<sub>3</sub>·H<sub>2</sub>O) and the carrier polymaltose and is available in solid form as a film-coated or chewable tablet and in liquid form as a syrup, drinkable solution, or drops.  It is used for treating [[Medicine:Iron deficiency|iron deficiency]] without anemia (latent iron deficiency) or with [[Medicine:Iron-deficiency anemia|anemia]] (apparent iron deficiency). Prior to administration, the iron deficiency should be diagnostically established and verified via laboratory tests (e.g., low [[Biology:Ferritin|ferritin]] concentration, low [[Medicine:Transferrin saturation|transferrin saturation]]).

The drug has been on the market since 1978 and is approved in over 85 countries. In many countries it is known with brand name Maltofer.

== Pharmacology ==

=== Mode of action ===
The drug is absorbed in the small intestine, primarily in the [[Biology:Duodenum|duodenum]] and [[Biology:Jejunum|jejunum]]. Absorption occurs via a controlled, active mechanism. No passive diffusion takes place, which ensures that practically no unbound (to [[Chemistry:Transferrin|transferrin]]) iron reaches the blood.<ref name=Geisser2007/> The absorbed iron is primarily stored in the [[Biology:Liver|liver]] as ferritin (protein used for iron storage) and subsequently made available to the body for various functions, primarily for incorporation into the red blood cells' [[Biology:Hemoglobin|hemoglobin]], thereby transporting oxygen in the blood.

=== Pharmacodynamics ===
The utilization and absorption by the erythrocytes of the iron administered orally in the form of iron polymaltose complex is correlated with the absorption in the intestines, whereby the relative absorption decreases with increased dosage and the more severe the iron deficiency, the greater the Absorption.<ref name=Geisser2011/> As with all oral iron preparations, only about 10-15% of the iron is absorbed.<ref name=Kaltwasser1987/> A dose of 100&nbsp;mg of iron is thus necessary in order for 10&nbsp;mg to be absorbed.

=== Pharmacokinetics ===
After administration, the maximum absorption capacity is reached already after 30 minutes and continuously increasing absorption can be observed over 24 hours.<ref name=Geisser2011/> The non-absorbed iron is excreted via the stool.

=== Effectiveness, safety ===
The effectiveness and safety have been investigated and documented in numerous clinical studies and in various patient populations.<ref name=Toblli2007/> This has included children, young people, adults, and the elderly, in addition to pregnant women and breastfeeding mothers.

==== Important clinical studies ====

===== Study in pregnant women =====
[[Randomized controlled trial|Randomized]], open, multicenter, controlled study in pregnant women affected by iron deficiency anemia. INTERVENTION: Iron polymaltose 100&nbsp;mg 2x a day in comparison to iron sulfate 100&nbsp;mg 2x a day.  STUDY DURATION: 90 days. RESULTS: hemoglobin improvement after 90 days by 2.16g/dL (iron polymaltose) and 1.93g/dL (iron sulfate). Ferritin levels after 90 days: 17.9&nbsp;ng/mL (iron polymaltose), 15.7&nbsp;ng/mL (iron sulfate). Side-effects observed in 29.3% of patients receiving iron polymaltose and 56.4% of those receiving iron sulfate.<ref name=Ortiz2011/>

===== Study in children =====
Randomized, open study in children affected by iron deficiency anemia. INTERVENTION: Iron polymaltose 5&nbsp;mg/kg body weight in one administration a day, compared to iron sulfate 5&nbsp;mg/kg body weight, divided up over 2 administrations a day. STUDY DURATION: 4 months. RESULTS: hemoglobin improvement after 4 months by 2.3g/dL (iron polymaltose) and 3g/dL (iron sulfate). Fewer gastrointestinal side-effects with iron polymaltose. The mean acceptance value after 4 months was higher with iron polymaltose than with iron sulfate.<ref name=Yasa2011/>

===== Study in adults =====
Randomized, multicenter, double-blind study in adults affected by iron deficiency anemia. INTERVENTION: Iron polymaltose 100&nbsp;mg 2x a day in comparison to iron sulfate 60&nbsp;mg 3x a day.  STUDY DURATION: 9 weeks. RESULTS: hemoglobin improvement in both groups after 3, 6, and 9 weeks, whereby after 3 and 6 weeks, a significant improvement was observed in the iron sulfate group. After 9 weeks, comparable improvement in both groups. Side-effects occurred in 22% of patients receiving iron polymaltose and 25% of those receiving iron sulfate.<ref name=Langstaff1993/>

==== Contraindications ====
Iron polymaltose must not be used in the event of known [[Medicine:Hypersensitivity|hypersensitivity]] or intolerance to the active ingredient or one of the excipients. Iron preparations are not administered to treat anemia that is not associated with iron deficiency. Furthermore, iron preparations must not be used in the event of known iron overload or iron utilization disorders.

==== Interactions ====
Iron polymaltose must not be administered at the same time as parenteral iron preparations. No interactions with other medications or foods are known.

==== Side-effects ====
Commonly observed side-effects, occurring in 1 to 10% of cases, include stool discoloration, [[Medicine:Diarrhea|diarrhea]], nausea, and dyspepsia. Uncommon side-effects, occurring in 0.1 to 1% of cases, include [[Medicine:Constipation|constipation]], [[Medicine:Vomiting|vomiting]], [[Medicine:Abdominal pain|stomachache]], tooth discoloration, itchiness, and [[Medicine:Headache|headache]]. As very rare side-effects, occurring in 0.1 to 0.01% of cases, [[Medicine:Allergy|allergic]] reactions have been observed.

== Dosage and administration ==
The preparation is available in various galenic formulations: syrup, drops, drinkable solution, film-coated tablets, and chewable tables. The syrup, drops, or drinkable solution are preferable for children. The preparation is dosed according to age. The following general dosage guidelines apply (for iron deficiency with anemia):

* '''Premature babies:''' 2.5–5&nbsp;mg/kg body weight
* '''Children up to 1 year of age:''' 25–50&nbsp;mg
* '''Children 1–12 years of age:''' 50–100&nbsp;mg
* '''Young people age 12 and up and adults:''' 100–300&nbsp;mg
* '''Pregnant women:''' 100–300&nbsp;mg

The quantity of active ingredient per unit is 100&nbsp;mg of iron per chewable or film-coated tablet, 50&nbsp;mg of iron per 1mL of drops, 10&nbsp;mg of iron per 1mL of syrup, 100&nbsp;mg of iron per 1 drinkable solution (5mL).

Iron polymaltose should be taken with food, as this improves absorption.<ref name=Lundqvist2007/>

== Excipients ==
The preparation contains different excipients depending upon the galenic formulation.
* '''Chewable tablets:''' cyclamate, vanillin, fersip, aromatica, excip. pro compr.
* '''Drops:''' conserv'''.:''' E217, E219; sucrose, vanillin, aromatica, excip. ad solut.
* '''Syrup:''' conserv.: E216, E218; sucrose, vanillin, aromatica, excip. ad solut.
* '''Drinkable solution:''' conserv.: E217, E219; sucrose, vanillin, aromatica, fersip, excip. ad solut.
* '''Film-coated tablets:''' excip. pro compr.

== Packaging, storage ==
The preparation should be stored in its original packaging at room temperature (15-25&nbsp;°C) and consumed by the date printed on the packaging.

== Chemical properties ==

=== General information ===
{| class="wikitable"
|Generic name
|Iron(III)-hydroxide polymaltose complex // iron polymaltose
|-
|Other names
| iron(3+);(2R,3S,4R,5R)-2,3,4,5-tetrahydroxy-6-[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyhexanal;trihydroxide
|-
|Molecular formula
|<chem>C12H25FeO14</chem>
|-
|CAS number
|53858-86-9
|-
|ATC code
|B03AB05
|}

=== Information regarding active ingredient, properties ===
{| class="wikitable"
|Drug class
|Oral iron preparations
|-
|Molar mass
|449,163 g/mol  
|-
|Physical state
| Solid or liquid
|}

== References ==
{{reflist|refs=
<ref name=Geisser2007>{{cite journal|title=Safety and efficacy of iron(III)-hydroxide polymaltose complex / a review of over 25 years experience.|last1=Geisser|first1=P.|journal=Arzneimittelforschung|year=2007|volume=57|issue=6A|pages=439–452|pmid=17691594|doi=10.1055/s-0031-1296693}}</ref>
<ref name=Geisser2011>{{cite journal|title=The pharmacokinetics and pharmacodynamics of iron preparations.|last1=Geisser|first1=P|last2=Burckhardt|first2=S.|journal=Pharmaceutics|date=4 January 2011|volume=3|number=1|pages=12–33|pmid=24310424|doi=10.3390/pharmaceutics3010012|pmc=3857035|doi-access=free}}</ref>
<ref name=Ortiz2011>{{cite journal|title=Efficacy and safety of oral iron(III) polymaltose complex versus ferrous sulfate in pregnant women with iron-deficiency anemia: a multicenter, randomized, controlled study|last1=Ortiz|first1=R|others=et al.|journal= Journal of Maternal-Fetal and Neonatal Medicine|date=November 2011|volume=24|number=11|pages=1347–52|pmid=21859366|doi=10.3109/14767058.2011.599080|s2cid=25666373}}</ref>
<ref name=Yasa2011>{{cite journal|title=Efficacy, Tolerability, and Acceptability of Iron Hydroxide Polymaltose Complex versus Ferrous Sulfate: A Randomized Trial in Pediatric Patients with Iron Deficiency Anemia|last1=Yasa|first1=B|others=et al.|journal=International Journal of Pediatrics|year=2011|volume=2011|page=524520|pmid=22121379|doi=10.1155/2011/524520|pmc=3206382|doi-access=free}}</ref>
<ref name=Langstaff1993>{{cite journal|last1=Langstaff|first1=RJ|others=et al.|title=Treatment of iron-deficiency anaemia: a lower incidence of adverse effects with Ferrum Hausmann than ferrous sulphate|journal=British Journal of Clinical Research|year=1993|volume=4|pages=191–198}}</ref>
<ref name=Toblli2007>{{cite journal|title=Iron(III)-hydroxide polymaltose complex in iron deficiency anemia / review and meta-analysis|last1=Toblli|first1=JE|last2=Brignoli|first2=R|journal=Arzneimittelforschung|year=2007|volume=57|number=6A|pages=431–438|pmid=17691593|doi=10.1055/s-0031-1296692}}</ref>
<ref name=Kaltwasser1987>{{cite journal|title=Bioavailability and therapeutic efficacy of bivalent and trivalent iron preparations|last1=Kaltwasser|first1=JP|last2=Werner|first2=E|last3=Niechzial|first3=M|journal=Arzneimittelforschung|year=1987|volume=37|number=1A|pages=122–129|pmid=3566867}}</ref>
<ref name=Lundqvist2007>{{cite journal|title=Food interaction of oral uptake of iron / a clinical trial using 59Fe|last1=Lundqvist|first1=H|last2=Sjöberg|first2=F|journal=Arzneimittelforschung|year=2007|volume=57|number=6A|pages=401–416|pmid=17691590|doi=10.1055/s-0031-1296689}}</ref>
}}

== External links ==
* [https://pubchem.ncbi.nlm.nih.gov/compound/76960246 PubChem]

[[Category:Iron(III) compounds]]

{{Sourceattribution|Iron polymaltose}}