Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

L-Tryptophan 500 mg Ingredients & Drug Interactions

by Source Naturals

L-Tryptophan 500 mg label
See full label image
Capsule Category: Amino Acid/protein
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking L-Tryptophan 500 mg against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

L-Tryptophan 500 mg is a dietary supplement by Source Naturals with 2 active ingredients. Its ingredients are commonly taken for iron-deficiency anemia, low iron stores during pregnancy, fatigue from iron deficiency.Based on those ingredients, 1,078 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are L-Tryptophan, Iron. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against L-Tryptophan 500 mg by Source Naturals

Ask about any prescription or over-the-counter medication and we check it for interactions with L-Tryptophan 500 mg by Source Naturals — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of L-Tryptophan 500 mg by Source Naturals

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • “L-Tryptophan” is listed as a grouped ingredient — the label gives one combined amount (1.50 g) without saying how much of each component you get.

This product contains two active ingredients: iron and niacin, along with a group ingredient listed as L-tryptophan (whose individual components aren't detailed in our data). Iron is a mineral that your body needs to build red blood cells and carry oxygen.

Niacin, also called vitamin B3, is a B vitamin involved in energy metabolism and DNA repair. The capsule also contains several inactive ingredients — gelatin, silica, magnesium stearate, dibasic calcium phosphate, and microcrystalline cellulose — which are fillers, binders, and capsule materials.

Does it work?

Not established
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: mood, relaxation, and restful sleep.
  • We looked for evidence on: Anxiety, Depression, Postpartum depression, Premenstrual syndrome (PMS), Premenstrual dysphoric disorder (PMDD), Seasonal affective disorder (SAD) — and 3 related terms.
  • The closest evidence on file: Iron is rated "Insufficient Reliable Evidence To Rate" for Postpartum depression (Natural Medicines).

Iron is rated Effective for iron deficiency anemia and anemia of chronic disease, and for pregnancy-related iron deficiency; it is rated Possibly Effective for heart failure. Niacin is rated Likely Effective for pellagra (a vitamin deficiency disease) and Possibly Effective for HIV/AIDS-related cholesterol problems and metabolic syndrome.

We hold no effectiveness data for L-tryptophan from the product facts provided.

The evidence, ingredient by ingredient Iron L-tryptophan Niacin

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Iron is generally well tolerated at recommended doses, but excess iron can be toxic — use it only when there's a real need. The most common side effects are abdominal pain, constipation, diarrhea, nausea, and vomiting.

Rarely, oral iron has been associated with stomach ulcers. Iron is often recommended during pregnancy, but your prenatal care provider should guide the dose; it's also generally acceptable while breastfeeding at appropriate doses.

Niacin from food and standard prenatal vitamins is fine, but high-dose niacin supplements should be avoided unless prescribed. Common side effects from supplemental niacin include flushing (up to 70% of people), stomach upset, and elevated liver enzymes; serious but rare effects include liver damage, muscle breakdown, and blood clotting problems.

High-dose niacin can also raise blood sugar.

Side effects, ingredient by ingredient Iron L-tryptophan Niacin

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 2 of the 2 matched ingredients can interact with medications — Iron, Niacin.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; Parkinson's medications.
  • For scale: 767 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your doctor or pharmacist if you take levodopa (Parkinson's medication), quinolone or tetracycline antibiotics, bisphosphonates (bone drugs), methyldopa (blood-pressure medication), levothyroxine (thyroid hormone), antihypertensive drugs, anticoagulants or antiplatelets (blood thinners), diabetes medications, statins, allopurinol or probenecid (gout drugs), bile acid sequestrants (cholesterol drugs), mycophenolate mofetil (immunosuppressant), or penicillamine. All require dose separation or monitoring.

We could not check L-tryptophan's interactions because it doesn't list its individual components.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

This product combines iron and niacin, both with documented interactions with many common medications. If you take anything for blood pressure, diabetes, thyroid function, infections, gout, cholesterol, blood clotting, or gout prevention, check your exact medications with the tool on this page before starting.

Talk with your doctor or pharmacist about whether this product is right for you and how to space doses if you do take it.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 22, 2023.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about L-Tryptophan 500 mg, straight from the product label.

Brand Source Naturals
Barcode (UPC) 021078019848
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Mar 22, 2023
DSLD ID 273573
Product type Amino Acid/protein
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for L-Tryptophan 500 mg by Source Naturals, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s), 3 Capsule(s)
Maximum serving Sizes:
1 Capsule(s), 3 Capsule(s)
Servings per container
20
UPC/BARCODE
021078019848
IngredientAmount% DV
Iron600 mcg3%
L-Tryptophan1.5 g--
Niacin25 mg--

Other ingredients: Gelatin, Silica, Magnesium Stearate, Dibasic Calcium Phosphate, Microcrystalline Cellulose

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
FDA Statement of Identity

Dietary Supplement

Formulation

Mood, relaxation, sleep

Contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no preservatives, or artificial color, flavor or fragrance.

Formula

The essential amino acid L-tryptophan helps support relaxation, restful sleep, and positive mood. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response and sleep/wake cycles. L-Tryptophan also supports immune functions because it is the body's precursor to the kynurenines that regulate immunity. If needed, L-Tryptophan converts to niacin in the body, which supports circulation, a healthy nervous system, the metabolism of food, and the production of hydrochloric acid for the digestive system. Source Naturals L-Tryptophan is extremely pure and is regularly tested to ensure the highest standards of quality.

Suggested/Recommended/Usage/Directions

Suggested Use: 1 capsule three times daily, between meals and preferably with fruit juice. To support restful sleep, take an additional 3 capsules before bed.

Precautions

Do not use if either tamper-evident seal is broken or missing.

Keep out of the reach of children.

Caution: If you are pregnant, may become pregnant, breastfeeding, or are taking medications such as SSRIs or MAOIs consult your health care professional before using this product.

Warning: Accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under 6. Keep this product out of reach of children. In case of accidental overdose, call a doctor or poison control center immediately.

Storage

Store in a cool, dry place.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Brand IP Statement(s)

Copyright SOURCE NATURALS, INC.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

L-Tryptophan 500 mg by Source Naturals label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

L-Tryptophan 500 mg label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in L-Tryptophan 500 mg by Source Naturals

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container20 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Iron

Interacts with
80 drugs
600 mcg per serving

Iron is an essential mineral your body needs to make hemoglobin and carry oxygen in the blood. Supplements are mainly useful for treating or preventin...

Iron monograph & interactions

L-Tryptophan

Interacts with
394 drugs
1.5 g per serving

L-tryptophan is an essential amino acid the body uses to make serotonin and melatonin, and people take it to support sleep and mood. The evidence for...

L-Tryptophan monograph & interactions

Other (inactive) ingredients: Gelatin, Silica, Magnesium Stearate, Dibasic Calcium Phosphate, Microcrystalline Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Tryptophan 500 mg by Source Naturals Drug Interactions

Want to check YOUR meds against L-Tryptophan 500 mg?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
1,078Drugs
248 Major 829 Moderate 1 Minor

Ingredients driving the most interactions

L-Tryptophan 394
Iron 80

Individual Drug Interactions

The ingredients in L-Tryptophan 500 mg interact with 1,078 drugs. Click any drug to see the details.

2 of the 2 ingredients in L-Tryptophan 500 mg interact with drugs. Each result below shows which ingredient is responsible. L-Tryptophan Iron

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Tryptophan 500 mg with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

L-Tryptophan2 drug types · 394 drugs

Cns Depressants

Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Clinical research shows that L-tryptophan can cause fatigue and drowsiness.

Likelihood Probable Evidence B
Serotonergic Drugs

Theoretically, combining L-tryptophan with serotonergic drugs might cause additive serotonergic effects.
L-tryptophan is a precursor to serotonin. Theoretically, combining serotonergic drugs with L-tryptophan might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders.

Likelihood Possible Evidence D
L-Tryptophan full monograph & interactions

Iron13 drug types · 80 drugs

Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and iron can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, iron containing products.

Likelihood Probable Evidence D
Bisphosphonates

Iron reduces the absorption of bisphosphonates.
Advise patients that doses of bisphosphonates should be separated by at least two hours from doses of all other medications, including supplements such as iron. Divalent cations, including iron, can decrease absorption of bisphosphonates by forming insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence D
Denosumab (Prolia, Others)

Administration of intravenous iron within one month of denosumab administration might increase the risk of severe hypophosphatemia and hypocalcemia.
A case of severe hypocalcemia (albumin corrected calcium 6.88 mg/dL, ionized calcium 3.68 mg/dL) and hypophosphatemia (<0.5 mg/dL) with respiratory acidosis, QT interval prolongation, and nonsustained ventricular tachycardia was reported in a 76-year-old male who had received an iron polymaltose infusion within 2 weeks of a subcutaneous injection of denosumab. Serum parathyroid hormone was also elevated (348 pg/mL). Subsequent iron infusions with iron polymaltose and ferric carboxymaltose were followed by transient hypophosphatemia, but without hypocalcemia. Additionally, a literature review describes 6 additional cases of hypophosphatemia and hypocalcemia in patients 52-92 years of age who had been administered intravenous iron as either ferric carboxymaltose or iron polymaltose and subcutaneous denosumab within 1-4 weeks of each other.

Likelihood Possible Evidence D
Dolutegravir (Tivicay)

Iron might decrease dolutegravir levels by reducing its absorption.
Advise patients to take dolutegravir at least 2 hours before or 6 hours after taking iron. Pharmacokinetic research shows that iron can decrease the absorption of dolutegravir from the gastrointestinal tract through chelation. When taken under fasting conditions, a single dose of ferrous fumarate 324 mg orally along with dolutegravir 50 mg reduces overall exposure to dolutegravir by 54%.

Likelihood Probable Evidence B
Integrase Inhibitors

Theoretically, taking iron along with integrase inhibitors might decrease the levels and clinical effects of these drugs.
Iron is a divalent cation. There is concern that iron may decrease the absorption of integrase inhibitors from the gastrointestinal tract through chelation. One pharmacokinetic study shows that iron can decrease blood levels of the specific integrase inhibitor dolutegravir through chelation. Also, other pharmacokinetic research shows that other divalent cations such as calcium can decrease the absorption and levels of some integrase inhibitors through chelation.

Likelihood Possible Evidence D
Levodopa

Iron might decrease levodopa levels by reducing its absorption.
Advise patients to separate doses of levodopa and iron as much as possible. There is some evidence in healthy people that iron forms chelates with levodopa, reducing the amount of levodopa absorbed by around 50%. The clinical significance of this hasn't been determined.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Iron might decrease levothyroxine levels by reducing its absorption.
Advise patients to separate levothyroxine and iron doses by at least 2 hours. Iron can decrease the absorption and efficacy of levothyroxine by forming insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence B
Methyldopa (Aldomet)

Iron might decrease methyldopa levels by reducing its absorption.
Advise patients to separate methyldopa and iron doses by at least 2 hours. Iron can decrease the absorption of methyldopa from the gastrointestinal tract through chelation, resulting in increases in blood pressure.

Likelihood Probable Evidence B
Mycophenolate Mofetil (Cellcept)

Theoretically, iron might decrease mycophenolate mofetil levels by reducing its absorption.
Advise patients to take iron 4-6 hours before, or 2 hours after, mycophenolate mofetil. It has been suggested that a decrease of absorption is possible, probably by forming nonabsorbable chelates. However, mycophenolate pharmacokinetics are not affected by iron supplementation in available clinical research.

Likelihood Unlikely Evidence D
Penicillamine (Cuprimine, Depen)

Iron might decrease penicillamine levels by reducing its absorption.
Advise patients to separate penicillamine and iron doses by at least 2 hours. Oral iron supplements can reduce absorption of penicillamine by 30% to 70%, probably due to chelate formation. In people with Wilson's disease, this interaction has led to reduced efficacy of penicillamine.

Likelihood Probable Evidence D
Quinolone Antibiotics

Iron might decrease levels of quinolone antibiotics by reducing their absorption.
Advise patients to separate quinolone antibiotics and iron doses by at least 2 hours. Iron decreases the absorption of quinolones due to formation of insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence D
Tetracycline Antibiotics

Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Advise patients to take iron at least 2 hours before or 4 hours after tetracycline antibiotics. Concomitant use can decrease absorption of tetracycline antibiotics from the gastrointestinal tract by 50% to 90%.

Likelihood Probable Evidence D
Chloramphenicol

Theoretically, taking chloramphenicol with iron might reduce the response to iron therapy in iron deficiency anemia.
Chloramphenicol interferes with erythrocyte maturation. However, since chloramphenicol isn't usually taken for prolonged periods, this isn't likely to be clinically significant.

Likelihood Unlikely Evidence D
Iron full monograph & interactions
The maker

Brand information

Manufacturer and brand details for L-Tryptophan 500 mg, from the product label.

Source Naturals

Name
Source Naturals, Inc.
Street Address
P. O. Box 2118
City
Santa Cruz
State
CA
ZipCode
95062
Web Address
www.sourcenaturals.com
Pharmacist Counseling Corner

L-Tryptophan 500 mg by Source Naturals: Common Questions

Does L-Tryptophan 500 mg by Source Naturals interact with any medications?
Yes. Based on its ingredients, L-Tryptophan 500 mg has a known interaction with 1,078 medications, including 248 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Tryptophan 500 mg contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is iron safe to take while I'm pregnant or breastfeeding?
Iron is often recommended during pregnancy, but your prenatal care provider should guide the dose. It's generally acceptable while breastfeeding at appropriate doses, but talk with your doctor or pharmacist about what's right for your situation.
What are the most common side effects I might experience?
From iron, you might get abdominal pain, constipation, diarrhea, nausea, or vomiting. From niacin, flushing (a warm, flushed feeling) is very common — up to 70% of people experience it — along with stomach upset and elevated liver enzymes. These effects often settle within a couple of weeks.
Why do I need to space iron doses apart from other medications?
Iron forms chemical complexes with certain medications in your digestive tract, which blocks absorption of the drug and makes it less effective. Separating doses by 2 to 6 hours prevents that from happening.
Can niacin raise my blood sugar?
Yes. Niacin can increase blood glucose levels in a dose-dependent way, which may reduce how well diabetes medications work. If you have diabetes or prediabetes, discuss this product with your doctor before starting.
What does iron do in this product?
Iron helps your body build red blood cells and carry oxygen. It's effective for iron deficiency anemia, anemia from chronic disease, and pregnancy-related iron deficiency, and possibly helpful for heart failure.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

L-Tryptophan 500 mg label
Go deeper

The Full Monographs Behind L-Tryptophan 500 mg’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Iron

Interacts with 80 drugs

Iron is an essential mineral your body needs to make hemoglobin and carry oxygen in the blood. Supplements are mainly useful for treating or preventing iron deficiency and iron-deficiency an...

Read the full Iron monograph → Herb & supplement monograph

L-tryptophan

Interacts with 394 drugs

L-tryptophan is an essential amino acid the body uses to make serotonin and melatonin, and people take it to support sleep and mood. The evidence for supplement use is limited and mixed, and...

Read the full L-tryptophan monograph → Herb & supplement monograph

Niacin

Interacts with 727 drugs

Niacin (vitamin B3) is an essential nutrient your body needs for energy and metabolism, and deficiency is uncommon in most developed countries. Prescription-strength niacin has been used to...

Read the full Niacin monograph →
Sources

Sources & How We Checked

L-Tryptophan 500 mg's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 156 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Iron 72 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Bruner AB, Joffe A, Duggan AK, et al. Randomized study of cognitive effects of iron supplementation in non- anaemic iron-deficient adolescent girls. Lancet 1996;348:992-6.
  3. Ullen H, Augustsson K, Gustavsson C, Steineck G. Supplementary iron intake and risk of cancer: reversed causality? Cancer Lett 1997;114:215-6.
  4. Reunanen A, Takkunen H, Knekt P, et al. Body iron stores, dietary iron intake and coronary heart disease mortality. J Intern Med 1995;238:223-30. PubMed
  5. Lund EK, Wharf SG, Fairweather-Tait SJ, Johnson IT. Oral ferrous sulfate supplements increase the free radical-generating capacity of feces from healthy volunteers. Am J Clin Nutr 1999;69:250-5.
  6. Rehman A, Collis CS, Yang M, et al. The effects of iron and vitamin C co-supplementation on oxidative damage to DNA in healthy volunteers. Biochem Biophys Res Comm 1998;246:293-8. PubMed
  7. Klipstein-Grobusch K, Grobbee DE, den Breeijen JH, et al. Dietary iron and risk of myocardial infarction in the Rotterdam Study. Am J Epidemiol 1999;149:421-8. PubMed
  8. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  9. Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
  10. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  11. Campbell N, Paddock V, Sundaram R. Alteration of methyldopa absorption, metabolism, and blood pressure control by ferrous sulfate and ferrous gluconate. Clin Pharmacol Ther 1988;43:381-6..
  12. Schumann K, Borch-Iohnsen B, Hentze MW, Marx JJ. Tolerable upper intakes for dietary iron set by the US Food and Nutrition Board (commentary). Am J Clin Nutr 2002;76:499-500. PubMed
  13. Tuomainen TP, Punnonen K, Nyyssonen K, Salonen JT. Association between body iron stores and the risk of acute myocardial infarction in men. Circulation 1998;97:1461-6.. PubMed
  14. Salonen JT, Nyyssonen K, Korpela H, et al. High stored iron levels are associated with excess risk of myocardial infarction in Eastern Finnish men. Circulation 1992;86:803-11.. PubMed
  15. Campbell NRC, Hasinoff B. Ferrous sulfate reduces levodopa bioavailability: Chelation as a possible mechanism. Clin Pharmacol Ther 1989;45:220-5.. PubMed
  16. Campbell NRC, Hasinoff BB, Stalts H, et al. Ferrous sulfate reduces thyroxine efficacy in patients with hypothyroidism. Ann Int Med 1992;117:1010-3.. PubMed
  17. Kiechl S, Willeit J, Egger G, et al. Body iron stores and the risk of carotid atherosclerosis: prospective results from the Bruneck study. Circulation 1997;96:3300-07. PubMed
  18. Comparison of oral iron supplements. Pharmacist's Letter / Prescriber's Letter 2008;24(8):240811.
  19. Tran T., Wax J. R., Philput C., Steinfeld J. D., Ingardia C. J. Intentional iron overdose in pregnancy--management and outcome. J Emerg Med 2000;18(2):225-228. PubMed
  20. Toblli J. E., Brignoli, R. Iron(III)-hydroxide polymaltose complex in iron deficiency anemia / review and meta-analysis. Arzneimittelforschung 2007;57(6A):431-438. PubMed
  21. Köpcke W., Sauerland M. C. Meta-analysis of efficacy and tolerability data on iron proteinsuccinylate in patients with iron deficiency anemia of different severity. Arzneimittelforschung 1995;45(11):1211-1216.
  22. Campbell N. R., Campbell R. R., Hasinoff B. B. Ferrous sulfate reduces methyldopa absorption: methyldopa: iron complex formation as a likely mechanism. Clin Invest Med 1990;13(6):329-332.
  23. Morii M., Ueno K., Ogawa A., Kato R., Yoshimura H., Wada K., Hashimoto H., Takada M., Tanaka K., Nakatani T., Shibakawa M. Impairment of mycophenolate mofetil absorption by iron ion. Clin Pharmacol Ther 2000;68(6):613-616. PubMed
  24. Gelone D. K., Park J. M., Lake K. D. Lack of an effect of oral iron administration on mycophenolic acid pharmacokinetics in stable renal transplant recipients. Pharmacotherapy 2007;27(9):1272-1278. PubMed
  25. Ducray P. S., Banken L., Gerber M., Boutouyrie B., Zandt H. Absence of an interaction between iron and mycophenolate mofetil absorption. Br J Clin Pharmacol 2006;62(4):492-495. PubMed
  26. Lorenz M., Wolzt M., Weigel G., Puttinger H., Hörl W. H., Födinger M., Speiser W., Sunder-Plassmann G. Ferrous sulfate does not affect mycophenolic acid pharmacokinetics in kidney transplant patients. Am J Kidney Dis 2004;43(6):1098-1103. PubMed
  27. Osman M. A., Patel R. B., Schuna A., Sundstrom W. R., Welling P. G. Reduction in oral penicillamine absorption by food, antacid, and ferrous sulfate. Clin Pharmacol Ther 1983;33(4):465-470. PubMed
  28. Michael, B., Coyne, D. W., Fishbane, S., Folkert, V., Lynn, R., Nissenson, A. R., Agarwal, R., Eschbach, J. W., Fadem, S. Z., Trout, J. R., Strobos, J., and Warnock, D. G. Sodium ferric gluconate complex in hemodialysis patients: adverse reactions compar
  29. Zhang, X., Ouyang, J., Wieczorek, R., and DeSoto, F. Iron medication-induced gastric mucosal injury. Pathol.Res Pract 2009;205(8):579-581. PubMed
  30. Barbieri, P. G. [To-day exposure to occupational carcinogens and their effects. The experience of the rubber industry, iron metallurgy, asphalt work and aviculture]. Epidemiol.Prev 2009;33(4-5 Suppl 2):94-105.
  31. Macedo, A. and Cardoso, S. [Routine iron supplementation in pregnancy]. Acta Med Port. 2010;23(5):785-792.
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