Drug Interaction:
Iron containing products include-
Ferrous Sulphate, Ferrous gluconate,Ferrous fumerate, Polysaccharide -Iron Complex, Iron with Vitamin C
Refer - Ferrous Fumarate
Interacting drugs - summary
+ Iron salts
Antacids
GI absorption of iron decreased
Ascorbic acid
ascorbic acid enhance the absorption of iron from GI tract
however this increase not significant
Chloramphenicol
serum levels increased
Cimetidine
GI absorption of iron reduced
Iron salts +
Levodopa
levodopa appears to form chelates with iron salts,
decreasing levodopa absorption of serum levels
Methyldopa
extent of methyldopa absorption e decreased
possibly resulting decreased efficacy
Penicillamine
marked reduction in GI absorption of penicillamine occur
possibly due to chelation
Quinolones
GI absorption of quinolones e decreased due to formation
of ferric-ion-quinolone complex
Iron salts + Tertracycline or Tetrcycline + Iron salts
Coadministration decrease absorption and serum levels
of Tetracyclins. Absorption of iron salts decreased
Drug/food interactions-
Eggs and milk inhibit iron absorption.
Coffee and tea consumed with a meal or 1 hour after a meal may siginificantly inhibit the absorpion of dietary iron.
Administration of calcium and iron supplements with food can educe ferrous sulfate absorption by one-third
If combined iron and calcium supplementation is required, iron absorption is not decreased
if calcium carbonate is used and the supplements are taken between meals.
Indication:
Iron containing products include-
Ferrous Sulphate, Ferrous gluconate,Ferrous fumerate, Polysaccharide -Iron Complex, Iron with Vitamin C
Refer - Ferrous Fumarate
Interacting drugs - summary
+ Iron salts
Antacids decr GI absorption of iron decreased Ascorbic acid incr ascorbic acid enhance the absorption of iron from GI tract however this increase not significant Chloramphenicol incr serum levels increased Cimetidine decr GI absorption of iron reduced
Iron salts +
Levodopa decr levodopa appears to form chelates with iron salts, decreasing levodopa absorption of serum levels Methyldopa decr extent of methyldopa absorption e decreased possibly resulting decreased efficacy Penicillamine decr marked reduction in GI absorption of penicillamine occur possibly due to chelation Quinolones decr GI absorption of quinolones e decreased due to formation of ferric-ion-quinolone complex Iron salts } + decr Coadministration decrease absorption and serum levels Tertracycline of Tetracyclins. Absorption of iron salts decreased ------------------ Tetrcycline } + decr Iron salts
Adverse Reaction:
GI irritation, nausea, vomiting, constipation, diarrhea, Stools appear darker in color Iron containg liquids may cause temporary staining of teeth. Dilute the liquid to reduce this possibility When iron containg products are given to infants, some darkening of the membrane covering the teeth may occur Overdosage and haemosiderosis. Abdominal pain, nausea, vomiting, diarrhoea or constipation.
Contra-Indications:
Repeated blood transfusion,anaemia not due to iron defeciency,iron storage/absorption diseases, haemoglobinopathies. Hemochromoatosis , hemosiderosis , hemolytic anemias Warning- Chronic iron intake - individuals with normal iron balance should not take iron chronically Special precautions: G.I.disease, infection. Intolerance- discontinue use if symptoms of intolerance appear. G I effects- occasional GI discomfort, such as nausea, may be minimized by taking with meals and slowly increasing to the recommended dosage Tartrazine sensitivity - Some of these products contain tartrazine which may cause allergic type reactions ( including bronchial asthma ) in susceptible individuals. Although such incidence of tatrazine sensitivity is low, it is frequently seen in patients who have aspirin sensitivity sensitivity Sulfite sensitivity- Some of the products contain sulfites which may cause allergic type reactions (eg. hives, itching, wheezing, anaphylaxis ) in cetain susceptible patients. Although such incidences are low, it is seen more frequently in asthamtics, or in atopic nonasthmatic persons.
Dosages/ Overdosage Etc:
Anemias
Dosage-
1 cap twice daily
Overdosage-
Oral lethal dose of elemental iron is about 200 to 250mg/kg , however, considerably less has been fatal Symptoms may be present when 30 to 60mg/kg is ingested
Acute poisoning will produce symptoms in four stages-
1. within 1 to 6 hours - lethargy , nausea, vomiting, abdominal pain, tarry stools, weak rapid pulse,hypotension, dehydration , acidosis, coma
2. if not immediately fatal, symptoms may subside for about 24 hours
3. symptoms return 12 to 48 hrs after ingestion and may include -
diffuse vascular congestion, pulmonary edema, shock, acidosis, convulsions, anuria, hyperthermia death
4. if patient survives in 2 to 6 weeks after ingestion, pyloric or antral stenosis, hepatic cirrhosis and CNS damage may be seen.
Treatment-
Maintain proper airway, respiration and circulation
If the patient is a candidate for emesis, induce with syrup of ipecac, follow with gastric lavage using tapid water or 1% to 5% sodium carbonate to convert the ferrous sulfate to ferrous carbonate which is poorly absorbed and less irritating
Systemic chealtion therapy with deferoxamine is generally recommended for patients with serum iron levels > 300mg/dl
Patient Information:
Ref - USP PDI Vol II 17th Edition (1997)
IRON SUPPLEMENTS
1.Allergies-
Tell your doctor if you have ever had any unusual or allergic reaction to
Iron medicines. Also tell your healthcare care professional if you are allergic
to any other substances such as foods. preservatives or dyes.
2.Pregnancy-
During the first 3 months of pregnancy, a proper diet usually provides
enough iron. However, during the last 6 months in order to meet the increased
needs of the developing baby, an iron supplement may be recommended by
your doctor.
However, taking large amounts of dietary supplement during pregnancy
may be harmful to the mother and/or fetus and should be avoided
3. Breast-feeding-
Taking large amounts of dietary supplements while breast feeding may be harmful
to the mother and infant and should be avoided
4.Children-
It is important to follow the directions given by the doctor, carefully since iron
overdose in children is especially dangerous
5.Older adults-
Problems in older patients have not been reported with normal intake of
daily recommended amounts. However, only your doctor can decide if you
need iron supplement and how much you can take.
6. Other medicines-
Tell your doctor if you are using any of the following -
Acetohydroxamic acid - eg. Lithostat - use with iron supplement may make
the iron less effective
Antacids- use with iron supplements may make the iron supplements
less effective. Iron supplements should be taken 1 or 2 hours before
or after antacids.
Dimercaparol- iron supplements and dimercaprol may combine in the
body to form harmful iron chemical.
Etidronate or
Fluoroquinolone-ciprofloxacin, enoxacin, lomefloxacin, norfloxacin, ofloxacin or
Tetracycline( taken by mouth) - use with iron supplements may make these
medicines less effective. Iron supplements should be taken 2 hours before
or after these medicines
7. Other medical problems-
The presence of other medical problems may affect the use of iron
supplements. Make sure you tell your doctor if you have any other medical
problems especially-
Alcohol abuse or
Kidney infection or
Porphyria cutaneous tarda- higher blood levels of iron supplements may occur,
which may increase the chance of side effects.
Arthiritis or
Asthma or allergies or
Heart disease - injected form of iron may make the condition worse.
Colitis or other intestinal problems or
Iron overload conditions eg- hemochromatosis, hemosiderosis or
Stomach ulcer - iron supplements may make the conditions worse.
Pharmacology/ Pharmacokinetics:
Pharmacology:
Iron, an essential mineral, is a component of hemoglobin, myoglobin and a number of enzymes. Aproximately two-thirds of total body iron is in the circulating red blood cells, the major factor in oxygen transport. Pharmacokinetics: The average intake of iron is 18 to 20 mg/day, of which only 10% of iron is absorbed(1 to 2mg/day) Absorptionis enhanced (20 to 30) when storage iron is depleted or when erythropoiesis occurs at an increased rate. The daily loss of iron from urine, sweat and sloughing of intestinal mucosa is approx 0.5 to 1mg in healthy men. In mensrurating women approx 1 to 2mg is the normal daily loss.
Interaction with Food:
Eggs and milk inhibit iron absorption.
Coffee and tea consumed with a meal or 1 hour after a meal may siginificantly inhibit the absorpion of dietary iron.
Administration of calcium and iron supplements with food can educe ferrous sulfate absorption by one-third If combined iron and calcium supplementation is required, iron absorption is not decreased if calcium carbonate is used and the supplements are taken between meals.
