FeroSul Green Ingredients & Drug Interactions
by Major
What is this page for?
First and foremost: checking FeroSul Green 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
FeroSul Green is a dietary supplement by Major with 1 active ingredient. Its ingredients are commonly taken for iron-deficiency anemia, low iron stores during pregnancy, fatigue from iron deficiency.Based on those ingredients, 80 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Iron. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against FeroSul Green by Major
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AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of FeroSul Green by Major
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.
What’s inside
Full disclosure
FeroSul Green is a single-ingredient iron supplement containing ferrous sulfate, a form of iron commonly used to treat iron deficiency. The tablet also contains a number of inactive ingredients — microcrystalline cellulose, croscarmellose sodium, crospovidone, and several others — that serve as binders, disintegrants, and coating agents to hold the tablet together and help it dissolve.
Does it work?
Strong evidence
Iron supplements like this one are effective for iron deficiency anemia and anemia of chronic disease, and are effective for pregnancy-related iron deficiency when dosed appropriately under prenatal care. The evidence for iron in heart failure is less certain — it's rated as possibly effective, meaning the research so far suggests a potential benefit but isn't conclusive.
How safe is it?
Well-documented data
Ferrous sulfate is generally well tolerated at recommended doses, but excess iron can be toxic; supplements should be used only when there's a genuine need. The most common side effects are gastrointestinal — abdominal pain, constipation, diarrhea, nausea, and vomiting — though serious adverse effects from oral iron are rare.
Iron is often recommended in pregnancy and is generally considered acceptable while breastfeeding at appropriate doses, but your prenatal care provider or pharmacist should guide the dose in both cases.
Meds to double-check
Moderate interaction found
Before you take this product, check with your doctor or pharmacist if you use levodopa (for Parkinson's disease), quinolone or tetracycline antibiotics, bisphosphonates, methyldopa, levothyroxine, mycophenolate mofetil, or penicillamine — iron reduces how much your body absorbs each of these, and you may need to space doses several hours apart.
The bottom line
Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.
FeroSul Green is an effective choice if you have iron deficiency or your doctor has recommended iron supplementation. However, because iron binds to many medications and reduces their absorption, you'll need to space your doses carefully if you take blood-pressure medications, antibiotics, thyroid medication, bisphosphonates, or certain other drugs.
Check your exact medication list with the tool on this page, and talk with your doctor or pharmacist about timing before you start.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 28, 2019.
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
General information
Key facts about FeroSul Green, straight from the product label.
| Brand | Major |
|---|---|
| Barcode (UPC) | 309047591602 |
| Net contents | 100 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | May 28, 2019 |
| DSLD ID | 202141 |
| Product type | Mineral |
| Supplement form | Tablet Or Pill |
| Dietary claims / uses | Nutrient, All Other |
| Intended target group(s) | Children 4 or More Years of Age, Adult (18 - 50 Years) |
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 FeroSul Green by Major, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Iron | 65 mg | 361% |
| Ferrous Sulfate | 325 mg | -- |
Other ingredients: Microcrystalline Cellulose, Croscarmellose Sodium, Crospovidone, Hypromellose, Sodium Lauryl Sulfate, Stearic Acid, Polydextrose, Talc, FD&C Red #40 Lake, FD&C Blue #1 Lake, Silica, FD&C Yellow #5 Lake, Triglycerides, Titanium Dioxide, Polyethylene Glycol, Mineral Oil
Tap any ingredient to jump to its full detail below.
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.
General Statements
New Formula
Specially coated Easy-to-swallow tablet
USP
Formula
Ferrous Sulfate 325 mg (5 gr) of Ferrous Sulfate Provides 65 mg of elemental Iron per table
Product contains FD&C Yellow #5 Lake (Tartrazine) as a color additive.
Please Note: Each 325 mg tablet of ferrous sulfate supplies 65 mg of elemental Iron.
FDA Statement of Identity
Iron Supplement
Precautions
Product contains FD&C Yellow #5 Lake (Tartrazine) as a color additive.
If pregnant or breast-feeding, seek the advice of a health professional before use.
Warning: Accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under six. Keep this product out of reach of children. In case of accidental overdose, call a doctor or Poison Control Center immediately.
Do not exceed 2 tablets in 24 hours. Not for frequent or prolonged use except on the advice of a doctor.
Do not give to children under 12 years of age.
Do not exceed recommended dosage.
Do not use if inner seal is broken or missing.
Suggested/Recommended/Usage/Directions
Directions: Adults and children over 12 years of age: Take 1 tablet daily as a dietary supplement, preferably with a meal or as directed by a doctor.
Storage
Store at room temperature, USP. Do not expose to excessive heat or moisture.
General
Re-Order No: 866872 M-29 Rev. 09/17 12290-09-17
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
FeroSul Green by Major label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in FeroSul Green by Major
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Tablet(s) Dosage formTablet Or Pill Amounts shown are per serving.
Iron
Interacts with80 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 preventin...
Iron monograph & interactionsOther (inactive) ingredients: Microcrystalline Cellulose, Croscarmellose Sodium, Crospovidone, Hypromellose, Sodium Lauryl Sulfate, Stearic Acid, Polydextrose, Talc, FD&C Red #40 Lake, FD&C Blue #1 Lake, Silica, FD&C Yellow #5 Lake, Triglycerides, Titanium Dioxide, Polyethylene Glycol, Mineral Oil. These complete the product’s ingredient list but are not active constituents.
FeroSul Green by Major Drug Interactions
HelloPharmacist Interaction Report
FeroSul Green by Major contains ferrous sulfate, which interacts with a significant number of medications, most notably through its ability to bind to drugs in your stomach and reduce how much your body absorbs them.
The most serious documented interaction is with levodopa (used for Parkinson's disease), where iron can cut absorption by about half, and with several antibiotic classes — quinolones, tetracyclines — where the effect is similar or worse. Altogether, these interactions span 80 individual medications.
Read the full breakdown — every affected drug type, severity by severity
Iron reduces absorption of multiple drug types by forming insoluble complexes in your gastrointestinal tract. You'll need to space doses apart from quinolone antibiotics (at least 2 hours), tetracycline antibiotics (at least 2 hours before or 4 hours after iron), bisphosphonates used for bone health (at least 2 hours apart), the blood-pressure medication methyldopa, the thyroid medication levothyroxine, mycophenolate mofetil (an immunosuppressant), and penicillamine (used for Wilson's disease and rheumatoid arthritis).
All of these interactions are moderate in severity.
To find out whether any of your own medications are affected, use the interaction checker below with your complete medication list. Your doctor or pharmacist can help you time doses to minimize the interaction.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against FeroSul Green?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in FeroSul Green interact with 80 drugs. Click any drug to see the details.
1 of the 1 ingredient in FeroSul Green interact with drugs. Each result below shows which ingredient is responsible. Iron
AlendronateBinosto, Fosamax
How Alendronate interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBisphosphonates Moderate
Interaction Summary
Iron reduces the absorption of bisphosphonates.
Read the full Ferrous Sulfate + Alendronate interactionAlendronate Sodium
How Alendronate Sodium interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBisphosphonates Moderate
Interaction Summary
Iron reduces the absorption of bisphosphonates.
Read the full Ferrous Sulfate + Alendronate Sodium interactionAlendronate Sodium, CholecalciferolFosamax Plus D
How Alendronate Sodium, Cholecalciferol interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBisphosphonates Moderate
Interaction Summary
Iron reduces the absorption of bisphosphonates.
Read the full Ferrous Sulfate + Alendronate Sodium, Cholecalciferol interactionAmphotericin, TetracyclineMysteclin-F
How Amphotericin, Tetracycline interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateTetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Amphotericin, Tetracycline interactionBenserazide, LevodopaMadopar, Prolopa
How Benserazide, Levodopa interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateLevodopa Moderate
Interaction Summary
Iron might decrease levodopa levels by reducing its absorption.
Read the full Ferrous Sulfate + Benserazide, Levodopa interactionBictegravir, Emtricitabine, Tenofovir AlafenamideBiktarvy
How Bictegravir, Emtricitabine, Tenofovir Alafenamide interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Moderate
Interaction Summary
Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Read the full Ferrous Sulfate + Bictegravir, Emtricitabine, Tenofovir Alafenamide interactionBismuth Subsalicylate, Metronidazole, TetracyclineHelidac
How Bismuth Subsalicylate, Metronidazole, Tetracycline interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateTetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Bismuth Subsalicylate, Metronidazole, Tetracycline interactionCarbidopa, LevodopaDhivy, Rytary, Sinemet, Sinemet CR
How Carbidopa, Levodopa interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateLevodopa Moderate
Interaction Summary
Iron might decrease levodopa levels by reducing its absorption.
Read the full Ferrous Sulfate + Carbidopa, Levodopa interactionCarbidopa, Levodopa, EntacaponeStalevo
How Carbidopa, Levodopa, Entacapone interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateLevodopa Moderate
Interaction Summary
Iron might decrease levodopa levels by reducing its absorption.
Read the full Ferrous Sulfate + Carbidopa, Levodopa, Entacapone interactionChlorothiazide, MethyldopaAldochlor, Aldoclor 150, Aldoclor 250
How Chlorothiazide, Methyldopa interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateMethyldopa (aldomet) Moderate
Interaction Summary
Iron might decrease methyldopa levels by reducing its absorption.
Read the full Ferrous Sulfate + Chlorothiazide, Methyldopa interactionChlortetracyclineAureomycin
How Chlortetracycline interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateTetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Chlortetracycline interactionCinoxacinCinobac
How Cinoxacin interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateQuinolone Antibiotics Moderate
Interaction Summary
Iron might decrease levels of quinolone antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Cinoxacin interactionCiprofloxacinCiloxan, Cipro, Cipro IV, Cipro XR, Ciprobay, Otiprio
How Ciprofloxacin interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateQuinolone Antibiotics Moderate
Interaction Summary
Iron might decrease levels of quinolone antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Ciprofloxacin interactionClinafloxacinClinafloxacin
How Clinafloxacin interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateQuinolone Antibiotics Moderate
Interaction Summary
Iron might decrease levels of quinolone antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Clinafloxacin interactionCobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide FumarateGenvoya
How Cobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide Fumarate interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Moderate
Interaction Summary
Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Read the full Ferrous Sulfate + Cobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide Fumarate interactionDarunavir, Cobicistat, Emtricitabine, Tenofovir AlafenamideSymtuza
How Darunavir, Cobicistat, Emtricitabine, Tenofovir Alafenamide interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Moderate
Interaction Summary
Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Read the full Ferrous Sulfate + Darunavir, Cobicistat, Emtricitabine, Tenofovir Alafenamide interactionDemeclocyclineDeclomycin
How Demeclocycline interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateTetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Demeclocycline interactionDenosumabProlia, XGEVA
How Denosumab interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateDenosumab (prolia, Others) Moderate
Interaction Summary
Administration of intravenous iron within one month of denosumab administration might increase the risk of severe hypophosphatemia and hypocalcemia.
Read the full Ferrous Sulfate + Denosumab interactionDolutegravirTivicay
How Dolutegravir interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateDolutegravir (tivicay) Moderate
Interaction Summary
Iron might decrease dolutegravir levels by reducing its absorption.
Read the full Ferrous Sulfate + Dolutegravir interactionDolutegravir, Emtricitabine, Tenofovir AlafenamideDolutegravir, Emtricitabine, Tenofovir Alafenamide
How Dolutegravir, Emtricitabine, Tenofovir Alafenamide interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateDolutegravir (tivicay), Bictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Moderate
Interaction Summary
Iron might decrease dolutegravir levels by reducing its absorption.
Read the full Ferrous Sulfate + Dolutegravir, Emtricitabine, Tenofovir Alafenamide interactionDolutegravir, RilpivirineJuluca
How Dolutegravir, Rilpivirine interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateDolutegravir (tivicay) Moderate
Interaction Summary
Iron might decrease dolutegravir levels by reducing its absorption.
Read the full Ferrous Sulfate + Dolutegravir, Rilpivirine interactionDoripenemDoribax
How Doripenem interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateQuinolone Antibiotics, Tetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of quinolone antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Doripenem interactionDoxycyclineDoryx, Doxy, Doxy-D, Doxycin, Doxycycline Injection, Doxylin +6 more
How Doxycycline interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateTetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Doxycycline interactionDoxycycline HyclateActiclate, Acticlate Cap, Lymepak
How Doxycycline Hyclate interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateTetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Doxycycline Hyclate interactionDoxycycline MonohydrateErfacea
How Doxycycline Monohydrate interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateTetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Doxycycline Monohydrate interactionDoxycylineDoxychel
How Doxycyline interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateTetracycline Antibiotics Moderate
Interaction Summary
Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Read the full Ferrous Sulfate + Doxycyline interactionElvitegravir, Cobicistat, Emtricitabine, Tenofovir Disoproxil FumarateStribild
How Elvitegravir, Cobicistat, Emtricitabine, Tenofovir Disoproxil Fumarate interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Moderate
Interaction Summary
Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Read the full Ferrous Sulfate + Elvitegravir, Cobicistat, Emtricitabine, Tenofovir Disoproxil Fumarate interactionEmtricitabineEmtriva
How Emtricitabine interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Moderate
Interaction Summary
Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Read the full Ferrous Sulfate + Emtricitabine interactionEmtricitabine, Rilpivirine, TenofovirComplera
How Emtricitabine, Rilpivirine, Tenofovir interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Moderate
Interaction Summary
Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Read the full Ferrous Sulfate + Emtricitabine, Rilpivirine, Tenofovir interactionEmtricitabine, Rilpivirine, Tenofovir AlafenamideOdefsey
How Emtricitabine, Rilpivirine, Tenofovir Alafenamide interacts with FeroSul Green — through 1 ingredient. Tap an ingredient for the detail:
Ferrous SulfateBictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Moderate
Interaction Summary
Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Read the full Ferrous Sulfate + Emtricitabine, Rilpivirine, Tenofovir Alafenamide interactionEach ingredient & the kinds of drugs it affects
For each ingredient in FeroSul Green with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
Iron
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.
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.
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.
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%.
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.
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.
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.
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.
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.
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.
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.
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%.
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.
Brand information
Manufacturer and brand details for FeroSul Green, from the product label.
Major
See all Major products- Name
- Major Pharmaceuticals
- Street Address
- 17177 N Laurel Park Drive, Suite 233
- City
- Livonia
- State
- MI
- ZipCode
- 48152
- Phone Number
- (800) 616-2471
FeroSul Green by Major: Common Questions
Does FeroSul Green by Major interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Is ferrous sulfate safe to take during pregnancy?
Can I take this while breastfeeding?
What are the most common side effects?
Does this actually work for iron deficiency anemia?
How long does it take to see results?
Can I take this with my blood pressure or thyroid medication?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if FeroSul Green is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind FeroSul Green’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
FeroSul Green'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 72 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
- McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
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