Vitamin C Ingredients & Drug Interactions
by Muscle Feast
What is this page for?
First and foremost: checking Vitamin C 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
Vitamin C is a dietary supplement by Muscle Feast with 1 active ingredient. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 207 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Vitamin C by Muscle Feast
Ask about any prescription or over-the-counter medication and we check it for interactions with Vitamin C by Muscle Feast — and tell you which ingredient is responsible.
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 Vitamin C by Muscle Feast
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
Muscle Feast Vitamin C is a straightforward single-ingredient supplement: one capsule delivers vitamin C in a vegetable capsule with purified water and a cellulose-based binder. That's it — no fillers or other actives.
Does it work?
Moderate evidence
Our data shows vitamin C is effective for treating vitamin C deficiency itself. For several other conditions — anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections — the evidence rates as possibly effective, meaning the research suggests a benefit but isn't conclusive yet.
How safe is it?
Well-documented data
Vitamin C is generally well tolerated at normal dietary and supplement doses. High doses (above 2 grams daily) are where problems show up: abdominal cramps, heartburn, diarrhea, nausea, and vomiting are most common.
If you're prone to kidney stones, be aware that vitamin C can increase that risk. Rare serious effects like kidney damage have been reported with very high-dose infusions.
For pregnancy and breastfeeding, normal amounts from food and prenatal vitamins are fine. The safety data advises caution with high-dose supplements during pregnancy and lactation — talk to your doctor or pharmacist for personalized advice before taking a supplement at this strength.
Meds to double-check
Moderate interaction found
Double-check this product before starting if you take chemotherapy drugs (alkylating agents or antitumor antibiotics), estrogen-based birth control or hormone replacement therapy, warfarin or other blood thinners, levothyroxine for thyroid, the HIV drug indinavir, the antipsychotic fluphenazine, or aluminum-containing medications. All of these have documented Moderate interactions with vitamin C.
The bottom line
Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.
Vitamin C from Muscle Feast is a good choice if you're correcting a deficiency and have no drug interactions. If you take birth control, warfarin, thyroid medication, or any chemotherapy, check with your pharmacist first — this supplement can meaningfully affect how those drugs work.
Keep doses reasonable (under 2 grams daily) to avoid side effects.
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 Apr 11, 2022.
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 Vitamin C, straight from the product label.
| Brand | Muscle Feast |
|---|---|
| Net contents | 120 Veg Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Apr 11, 2022 |
| DSLD ID | 262487 |
| Product type | Vitamin |
| Supplement form | Capsule |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Women (not pregnant or lactating) |
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 Vitamin C by Muscle Feast, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Vitamin C | 950 mg | 1583% |
Other ingredients: Hydroxypropylmethylcellulose, Water, Purified
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.
Formula
Vitamin C (ascorbic acid) is an essential part of the human body's growth and development, aiding in the repair of all body tissues. This water-soluble vitamin is involved in the absorption of iron, the formation of collagen, and the maintenance of teeth, bones, and cartilage. Furthermore, studies have found that it supports the immune system and even aids in the wound healing.
Suggested/Recommended/Usage/Directions
Suggested use: As an adult dietary supplement, take one capsule per day or as directed by your physcian.
Seals/Symbols
Made in Our GMP Compliant Facility Made in an FDA Registered Facility
Ohio Family Owned Business
General Statements
SDVOSB Service Disabled Veteran Owned Small Business
FDA Statement of Identity
Dietary Supplement
Formulation
Immune support Vegan capsules Wellness support Anti-oxidant Essential vitamin
Precautions
Warning: This product is manufactured in a GMP compliant plant that processes milk.
Keep out of reach of children.
Do not exceed the recommended dose. Consult your physician before using this product.
Do not use this product if you are pregnant or nursing. Do not use this product if you are taking any prescription medication.
Do not use this product if you are under the age of 18.
Storage
Keep tightly closed in a cool, dry place away from sunlight.
FDA Disclaimer Statement
This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Vitamin C by Muscle Feast 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 Vitamin C by Muscle Feast
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Capsule(s) Dosage formCapsule Servings per container120 Amounts shown are per serving.
Vitamin C
Interacts with207 drugs
Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...
Vitamin C monograph & interactionsOther (inactive) ingredients: Hydroxypropylmethylcellulose, Water, Purified. These complete the product’s ingredient list but are not active constituents.
Vitamin C by Muscle Feast Drug Interactions
HelloPharmacist Interaction Report
Muscle Feast Vitamin C is a single-ingredient supplement that does interact with several medications.
The most serious concern is with chemotherapy drugs called alkylating agents and antitumor antibiotics — vitamin C's antioxidant properties may theoretically reduce how well these cancer treatments work, which is a Moderate severity issue. You should not take this supplement during chemotherapy without explicit approval from your oncologist.
Read the full breakdown — every affected drug type, severity by severity
Vitamin C also has Moderate interactions with hormonal birth control and hormone replacement therapy (estrogens can increase in your bloodstream by up to 55%), blood thinners like warfarin (especially at high doses), thyroid medication (levothyroxine), and the HIV drug indinavir. It can also increase aluminum absorption from aluminum-containing products and may lower levels of the antipsychotic fluphenazine.
Altogether, these interactions span 207 individual medications. If you take any prescription medication — especially birth control, warfarin, thyroid meds, cancer drugs, or HIV antiretrovirals — use the medication checker on this page to look up your exact drugs before you start this supplement.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Vitamin C?
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 Vitamin C interact with 207 drugs. Click any drug to see the details.
1 of the 1 ingredient in Vitamin C interact with drugs. Each result below shows which ingredient is responsible. Vitamin C
Acetaminophen, Chlorpheniramine, Dextromethorphan, PhenylpropanolamineMulti Symptom Cold Relief
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PseudoephedrineChildren's Tylenol Cold Plus Cough, Tylenol Cold Ex Strength
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interactionAcetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, SalicylamideRhinogesic GG
How Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interactionAcetaminophen, Chlorpheniramine, PhenylephrineAlka-Seltzer PLUS, Histex SR, Protid
How Acetaminophen, Chlorpheniramine, Phenylephrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Phenylephrine interactionAcetaminophen, Chlorpheniramine, Phenylephrine, SalicylamideRhinogesic, Rhinogesic JR
How Acetaminophen, Chlorpheniramine, Phenylephrine, Salicylamide interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Phenylephrine, Salicylamide interactionAcetaminophen, Chlorpheniramine, PhenylpropanolamineAlumadrine, Conex, Sinadrin Max Strength, Sinulin
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Phenylpropanolamine interactionAcetaminophen, Chlorpheniramine, Phenylpropanolamine, OpiumHista-Derfule
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Opium interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Opium interactionAcetaminophen, Chlorpheniramine, Phenylpropanolamine, PhenyltoloxamineNorel Plus
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Phenyltoloxamine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Phenyltoloxamine interactionAcetaminophen, Chlorpheniramine, PseudoephedrineAlka-Seltzer PLUS Liquid Gels, Children's Tylenol Cold, Codimal, Comtrex, Extra Strength Tylenol Allergy Sinus, Lorsin +3 more
How Acetaminophen, Chlorpheniramine, Pseudoephedrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Pseudoephedrine interactionAcetaminophen, ChlorzoxazoneAcetazone Forte, Extra Strength Tylenol Aches & Strains, Parafon Forte
How Acetaminophen, Chlorzoxazone interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorzoxazone interactionAcetaminophen, Chlorzoxazone, CodeineAcetazone Forte C8, Parafon Forte C8
How Acetaminophen, Chlorzoxazone, Codeine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorzoxazone, Codeine interactionAcetaminophen, CodeineTylenol No.3, Tylenol w/ Codeine
How Acetaminophen, Codeine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Codeine interactionAcetaminophen, Codeine, DoxylamineMersyndol
How Acetaminophen, Codeine, Doxylamine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Codeine, Doxylamine interactionAcetaminophen, Codeine, MethocarbamolAcetaminophen, Codeine, Methocarbamol, Robaxacet 8
How Acetaminophen, Codeine, Methocarbamol interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Codeine, Methocarbamol interactionAcetaminophen, Dexbrompheniramine, PseudoephedrineSinadrin Plus
How Acetaminophen, Dexbrompheniramine, Pseudoephedrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dexbrompheniramine, Pseudoephedrine interactionAcetaminophen, DextromethorphanTylenol Cough Ex Strength
How Acetaminophen, Dextromethorphan interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dextromethorphan interactionAcetaminophen, Dextromethorphan, Doxylamine, PseudoephedrineVicks NyQuil
How Acetaminophen, Dextromethorphan, Doxylamine, Pseudoephedrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dextromethorphan, Doxylamine, Pseudoephedrine interactionAcetaminophen, Dextromethorphan, Guaifenesin, PhenylephrineConar-A
How Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine interactionAcetaminophen, Dextromethorphan, Guaifenesin, PhenylpropanolamineAnatuss
How Acetaminophen, Dextromethorphan, Guaifenesin, Phenylpropanolamine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dextromethorphan, Guaifenesin, Phenylpropanolamine interactionAcetaminophen, Dextromethorphan, Guaifenesin, PseudoephedrineRobitussin Cold, Severe Cold, Suphedrine Cold/Cough
How Acetaminophen, Dextromethorphan, Guaifenesin, Pseudoephedrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dextromethorphan, Guaifenesin, Pseudoephedrine interactionAcetaminophen, Dextromethorphan, Phenylpropanolamine, PyrilamineTheracaps
How Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine interactionAcetaminophen, Dextromethorphan, PseudoephedrineAlka-Seltzer PLUS Flu Liquid Gels, Non Aspirin Cold Caps, Tylenol Cold, Tylenol Flu Daytime Ex Strength, Tylenol Flu Ex Strength
How Acetaminophen, Dextromethorphan, Pseudoephedrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dextromethorphan, Pseudoephedrine interactionAcetaminophen, Dichloralantipyrine, IsomethepteneAmidrine, Midchlor, Migquin, Migratine
How Acetaminophen, Dichloralantipyrine, Isometheptene interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dichloralantipyrine, Isometheptene interactionAcetaminophen, Dichloralphenazone, IsomethepteneMidrin
How Acetaminophen, Dichloralphenazone, Isometheptene interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dichloralphenazone, Isometheptene interactionAcetaminophen, Dichlorophenazone, IsometheptaneIsocom
How Acetaminophen, Dichlorophenazone, Isometheptane interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Dichlorophenazone, Isometheptane interactionAcetaminophen, DiphenhydramineTylenol PM, Tylenol PM Ex Strength
How Acetaminophen, Diphenhydramine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Diphenhydramine interactionAcetaminophen, Diphenhydramine, PseudoephedrineChildren's Tylenol Allergy, Cold Control, Contac Night Allergy Relief
How Acetaminophen, Diphenhydramine, Pseudoephedrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Diphenhydramine, Pseudoephedrine interactionAcetaminophen, Doxylamine, PseudoephedrineEx Strength Tylenol Sinus Nighttime
How Acetaminophen, Doxylamine, Pseudoephedrine interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Doxylamine, Pseudoephedrine interactionAcetaminophen, HydrocodoneAnexsia, Anodynos DHC, Azdone, Co-Gesic, Doucet, Lorcet +9 more
How Acetaminophen, Hydrocodone interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Hydrocodone interactionAcetaminophen, IbuprofenCombogesic
How Acetaminophen, Ibuprofen interacts with Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Ibuprofen interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Vitamin C 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.
Vitamin C
Alkylating Agents
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.
Aluminum
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.
Antitumor Antibiotics
Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.
Estrogens
Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.
Fluphenazine (Prolixin)
Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.
Indinavir (Crixivan)
Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.
Levothyroxine (Synthroid, Others)
Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.
Warfarin (Coumadin)
High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.
Acetaminophen (Tylenol, Others)
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.
Aspirin
Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.
Choline Magnesium Trisalicylate (Trilisate)
Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.
Niacin
Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.
Salsalate (Disalcid)
Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.
Brand information
Manufacturer and brand details for Vitamin C, from the product label.
Muscle Feast
See all Muscle Feast products- Name
- Muscle Feast
- Street Address
- 1320 Boston Road
- City
- Nashport
- State
- OH
- ZipCode
- 43830
- Phone Number
- (888) 734-3634
- Web Address
- www.musclefeast.com
Vitamin C by Muscle Feast: Common Questions
Does Vitamin C by Muscle Feast interact with any medications?
How can one product interact with so many drugs?
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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.
The Full Monographs Behind Vitamin C’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Vitamin C'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 51 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.
Vitamin C 51 references
- McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
- Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
- Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
- Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
- Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
- Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
- Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
- Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
- Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
- Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
- Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
- Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
- Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
- Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
- Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
- Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
- Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
- Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
- Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
- Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
- Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
- Vihtamaki T, Parantainen J, Koivisto AM, et al. Oral ascorbic acid increases plasma oestradiol during postmenopausal hormone replacement therapy. Maturitas 2002;42:129-35. PubMed
- Slain D, Amsden JR, Khakoo RA, et al. Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers. Pharmacotherapy 2005;25:165-70. PubMed
- Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
- Feetam CL, Leach RH, Meynell MJ. Lack of a clinically important interaction between warfarin and ascorbic acid. Toxicol Appl Pharmacol 1975;31:544-7. PubMed
- Weintraub M, Griner PF. Warfarin and ascorbic acid: lack of evidence for a drug interaction. Toxicol Appl Pharmacol 1974;28:53-6. PubMed
- Lee DH, Folsom AR, Harnack L, et al. Does supplemental vitamin C increase cardiovascular disease risk in women with diabetes? Am J Clin Nutr 2004;80:1194-200. PubMed
- Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-32. PubMed
- Ward NC, Hodgson JM, Croft KD, et al. The combination of vitamin C and grape-seed polyphenols increases blood pressure: a randomized, double-blind, placebo-controlled trial. J Hypertens 2005;23:427-34.. PubMed
- Prasad KN. Rationale for using high-dose multiple dietary antioxidants as an adjunct to radiation therapy and chemotherapy. J Nutr 2004;134:3182S-3S. PubMed
- Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
- Fairweather-Tait S, Hickson K, McGaw B, et al. Orange juice enhances aluminium absorption from antacid preparation. Eur J Clin Nutr. 1994;48(1):71-3.
- Gruenwald, J., Graubaum, H. J., Busch, R., and Bentley, C. Safety and tolerance of ester-C compared with regular ascorbic acid. Adv.Ther. 2006;23(1):171-178.
- Rahimi, R., Nikfar, S., Rezaie, A., and Abdollahi, M. A meta-analysis on the efficacy and safety of combined vitamin C and E supplementation in preeclamptic women. Hypertens.Pregnancy. 2009;28(4):417-434. PubMed
- Einerson, B., Nathorn, C., Kitiyakara, C., Sirada, M., and Thamlikitkul, V. The efficacy of ascorbic acid in suboptimal responsive anemic hemodialysis patients receiving erythropoietin: a meta-analysis. J Med.Assoc.Thai. 2011;94 Suppl 1:S134-S146.
- Li, G., Li, L., Yu, C., and Chen, L. Effect of vitamins C and E supplementation on Helicobacter pylori eradication: a meta-analysis. Br.J Nutr 2011;106(11):1632-1637.
- Chen X, Shen L, Gu X, et al. High-dose supplementation with vitamin C--induced pediatric urolithiasis: the first case report in a child and literature review. Urology. 2014;84(4):922-4. PubMed
- Sattar A, Willman JE, Kolluri R. Possible warfarin resistance due to interaction with ascorbic acid: case report and literature review. Am J Health Syst Pharm. 2013;70(9):782-6. PubMed
- Yaich S, Chaabouni Y, Charfeddine K, et al. Secondary oxalosis due to excess vitamin C intake: a cause of graft loss in a renal transplant recipient. Saudi J Kidney Dis Transpl. 2014;25(1):113-6. PubMed
- Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
- Rumbold A, Ota E, Nagata C, Shahrook S, Crowther CA. Vitamin C supplementation in pregnancy. Cochrane Database Syst Rev. 2015;(9):CD004072. PubMed
- Seo MS, Kim JK, Shim JY. High-dose vitamin C promotes regression of multiple pulmonary metastases originating from hepatocellular carcinoma. Yonsei Med J. 2015;56(5):1449-52. PubMed
- Skelin M, Lucijanic T, Amidzic Klaric D, et al. Factors Affecting Gastrointestinal Absorption of Levothyroxine: A Review. Clin Ther. 2017 Feb;39(2):378-403. PubMed
- Jiang K, Tang K, Liu H, Xu H, Ye Z, Chen Z. Ascorbic acid supplements and kidney stones incidence among men and women: a systematic review and meta-analysis. Urol J. 2019;16(2):115-120.
- Thomas S, Patel D, Bittel B, et al. Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical Trial. JAMA Netw Open. 2 PubMed
- Giffen MA, McLemore JL. Hyperoxalosis Secondary to Intravenous Vitamin C Administration as a Non-Allopathic Treatment for Cancer. Acad Forensic Pathol 2019;9(1-2):118-126. PubMed
- Maike A, Sturgill D, Gallan A. Oxalate Nephropathy in a Renal Transplant Recipient After Receiving High Dose Ascorbic Acid. Am J Med Sci 2021. PubMed
- Shen ZY, Chen YR, Wang MC, Chang SS. High-dose vitamin C-induced acute oxalate nephropathy in a renal transplant recipient: a case report and literature review. Asian J Surg 2022. PubMed
- Yanase F, Spano S, Maeda A, et al. Mega-dose sodium ascorbate: a pilot, single-dose, physiological effect, double-blind, randomized, controlled trial. Crit Care 2023;27(1):371. PubMed
- Sharma Y, Sumanadasa S, Shahi R, et al. Efficacy and safety of vitamin C supplementation in the treatment of community-acquired pneumonia: a systematic review and meta-analysis with trial sequential analysis. Sci Rep 2024;14(1):11846. PubMed
- Pejcic AV, Petrovic NZ, Djordjic MD, Milosavljevic MN. Vitamin C Levels in Pregnant Women and the Efficacy of Vitamin C Supplements in Preventing Premature Rupture of Membranes: A Systematic Review and Meta-Analysis. Balkan Med J 2024;41(4):248-260. PubMed
Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC