Sustained Release Vitamin C 500 mg Ingredients & Drug Interactions
by Bronson Laboratories
What is this page for?
First and foremost: checking Sustained Release Vitamin C 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
Sustained Release Vitamin C 500 mg is a dietary supplement by Bronson Laboratories 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 Sustained Release Vitamin C 500 mg by Bronson Laboratories
Ask about any prescription or over-the-counter medication and we check it for interactions with Sustained Release Vitamin C 500 mg by Bronson Laboratories — 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 Sustained Release Vitamin C 500 mg by Bronson Laboratories
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
This product contains one active ingredient: vitamin C, a water-soluble vitamin your body needs for immune function, collagen formation, and protection against oxidative stress. The supplement comes in a capsule form with inactive ingredients including gelatin, sucrose, corn starch, pharmaceutical glaze, and magnesium silicate.
Does it work?
Moderate evidence
Vitamin C is effective for preventing and treating vitamin C deficiency. The evidence also suggests it may be helpful for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections, though the data for these uses is not yet conclusive — rated possibly effective.
How safe is it?
Well-documented data
Vitamin C is generally well tolerated at normal doses. At very high doses — above 2,000 mg daily — it can cause abdominal cramps, heartburn, nausea, diarrhea, headache, and kidney stones in people prone to them.
This 500 mg sustained-release dose is much lower and unlikely to trigger those side effects in most people. For pregnancy and breastfeeding, normal amounts from food and prenatal vitamins are considered safe.
However, the safety data shows possibly unsafe for high-dose supplements in these situations — talk with your doctor before taking high-dose vitamin C if you're pregnant or nursing.
Meds to double-check
Moderate interaction found
Before you start, double-check with your pharmacist if you take estrogen-based medications (birth control, hormone replacement therapy), blood thinners like warfarin, thyroid medication (levothyroxine), the anti-HIV drug indinavir, the antipsychotic fluphenazine, chemotherapy drugs, or aluminum-containing products. 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 500 mg is a straightforward way to meet your daily needs, especially if you're not getting enough from food. It works well for deficiency and may help with a few other conditions.
The main caution is if you take birth control, blood thinners, thyroid medication, or chemotherapy — check with your pharmacist first because vitamin C can change how these drugs work.
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 Aug 23, 2013.
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 Sustained Release Vitamin C 500 mg, straight from the product label.
| Brand | Bronson Laboratories |
|---|---|
| Barcode (UPC) | 716563046026 |
| Net contents | 250 Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Aug 23, 2013 |
| DSLD ID | 24998 |
| Product type | Vitamin |
| Supplement form | Capsule |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | 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 Sustained Release Vitamin C 500 mg by Bronson Laboratories, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Vitamin C | 500 mg | 833% |
Other ingredients: Gelatin, Sucrose, Corn Starch, Pharmaceutical Glaze, Magnesium Silicate
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.
FDA Statement of Identity
Dietary Supplement
General Statements
Maintains a healthy immune system
Made in USA
VITAMIN FORMULAS EST 1960
General
46b REF 0213
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)
Discover the Bronson Difference(R)
Suggested/Recommended/Usage/Directions
Directions: As a dietary supplement for adults, 1 capsule daily or as directed by a health professional.
Precautions
WARNING: Consult a healthcare professional before taking this product if you are pregnant or nursing.
Keep out of reach of children.
Storage
Store at room temperature. Protect from light.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Sustained Release Vitamin C 500 mg by Bronson Laboratories 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 Sustained Release Vitamin C 500 mg by Bronson Laboratories
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Capsule(s) Dosage formCapsule 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: Gelatin, Sucrose, Corn Starch, Pharmaceutical Glaze, Magnesium Silicate. These complete the product’s ingredient list but are not active constituents.
Sustained Release Vitamin C 500 mg by Bronson Laboratories Drug Interactions
HelloPharmacist Interaction Report
Bronson Laboratories Sustained Release Vitamin C 500 mg contains one active ingredient — vitamin C — which does interact with a number of medications.
The most serious interactions we have on file are Moderate in severity.
Read the full breakdown — every affected drug type, severity by severity
Vitamin C can affect how your body handles estrogens (including birth control pills and hormone replacement therapy). Research shows vitamin C can raise estrogen levels by up to 55% in some cases, because it may prevent your body from breaking estrogen down as quickly as it normally would.
If you take any estrogen-based medication, talk to your doctor or pharmacist before starting this supplement.
Vitamin C also has documented Moderate interactions with blood thinners like warfarin — high doses may reduce how well they work — and with the anti-HIV drug indinavir. There are also Moderate concerns with thyroid medication (levothyroxine), certain chemotherapy drugs (alkylating agents and antitumor antibiotics), the antipsychotic fluphenazine, and aluminum-containing products.
Altogether, these interactions span 207 individual medications.
To be safe, check your exact medications with the search tool on this page before you start.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Sustained Release Vitamin C 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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Sustained Release Vitamin C 500 mg interact with 207 drugs. Click any drug to see the details.
1 of the 1 ingredient in Sustained Release Vitamin C 500 mg interact with drugs. Each result below shows which ingredient is responsible. Vitamin C
Alginic Acid, Aluminum HydroxideRafton
How Alginic Acid, Aluminum Hydroxide interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Alginic Acid, Aluminum Hydroxide interactionAltretamineHexalen
How Altretamine interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Altretamine interactionAluminum Acetate, Benzethonium ChlorideBuro-Sol Otic Solution
How Aluminum Acetate, Benzethonium Chloride interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Aluminum Acetate, Benzethonium Chloride interactionAluminum ChlorideAluminum Chloride, Anhydrol Forte, Driclor, Drysol
How Aluminum Chloride interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Aluminum Chloride interactionAluminum HydroxideAlu-Cap, Amphojel, Gaviscon
How Aluminum Hydroxide interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Aluminum Hydroxide interactionAluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #2
How Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAspirin, Aluminum Moderate
Interaction Summary
Acidification of the urine by vitamin C might increase aspirin levels.
Read the full Vitamin C + Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interactionAluminum Hydroxide, Aspirin, Magnesium HydroxideAscriptin
How Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAspirin, Aluminum Moderate
Interaction Summary
Acidification of the urine by vitamin C might increase aspirin levels.
Read the full Vitamin C + Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interactionAluminum Hydroxide, Magnesium Hydroxide (otc Drug)Maalox, Mucogel
How Aluminum Hydroxide, Magnesium Hydroxide (otc Drug) interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Aluminum Hydroxide, Magnesium Hydroxide (otc Drug) interactionAluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug)Mylanta
How Aluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug) interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Aluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug) interactionAluminum, CalciumDomeboro
How Aluminum, Calcium interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Aluminum, Calcium interactionAluminum, Magnesium (otc Drug)Almagel
How Aluminum, Magnesium (otc Drug) interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Aluminum, Magnesium (otc Drug) interactionAluminum, Magnesium Hydroxide (otc Drug)Wingel
How Aluminum, Magnesium Hydroxide (otc Drug) interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAluminum Moderate
Interaction Summary
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Read the full Vitamin C + Aluminum, Magnesium Hydroxide (otc Drug) interactionAspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #3
How Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium Hydroxide interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAspirin, Aluminum Moderate
Interaction Summary
Acidification of the urine by vitamin C might increase aspirin levels.
Read the full Vitamin C + Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium Hydroxide interactionBazedoxifene Acetate, Conjugated EstrogensDuavee
How Bazedoxifene Acetate, Conjugated Estrogens interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CEstrogens Moderate
Interaction Summary
Vitamin C might increase blood levels of estrogens.
Read the full Vitamin C + Bazedoxifene Acetate, Conjugated Estrogens interactionBendamustineBelrapzo, Treanda, Vivimusta
How Bendamustine interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Bendamustine interactionBendamustine HydrochlorideBendeka
How Bendamustine Hydrochloride interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Bendamustine Hydrochloride interactionBleomycinBlenoxane
How Bleomycin interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAntitumor Antibiotics Moderate
Interaction Summary
Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
Read the full Vitamin C + Bleomycin interactionBusulfanBusulfex, Myleran
How Busulfan interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Busulfan interactionCarboplatinParaplatin
How Carboplatin interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Carboplatin interactionCarmustineBiCNU, Gliadel, Gliadel Wafer
How Carmustine interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Carmustine interactionChlorambucilLeukeran
How Chlorambucil interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Chlorambucil interactionCisplatinPlatinol-AQ
How Cisplatin interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Cisplatin interactionConjugated EstrogensCenestin, Enjuvia, Premarin, Premarin Vaginal Cream
How Conjugated Estrogens interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CEstrogens Moderate
Interaction Summary
Vitamin C might increase blood levels of estrogens.
Read the full Vitamin C + Conjugated Estrogens interactionConjugated Estrogens, Medroxyprogesterone AcetatePremplus, Prempro
How Conjugated Estrogens, Medroxyprogesterone Acetate interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CEstrogens Moderate
Interaction Summary
Vitamin C might increase blood levels of estrogens.
Read the full Vitamin C + Conjugated Estrogens, Medroxyprogesterone Acetate interactionConjugated Estrogens, MeprobamatePMB 200, PMB 400
How Conjugated Estrogens, Meprobamate interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CEstrogens Moderate
Interaction Summary
Vitamin C might increase blood levels of estrogens.
Read the full Vitamin C + Conjugated Estrogens, Meprobamate interactionConjugated Estrogens, MethyltestosteronePremarin with Methyltestosterone
How Conjugated Estrogens, Methyltestosterone interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CEstrogens Moderate
Interaction Summary
Vitamin C might increase blood levels of estrogens.
Read the full Vitamin C + Conjugated Estrogens, Methyltestosterone interactionCyclophosphamideCytoxan, Neosar
How Cyclophosphamide interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Cyclophosphamide interactionCyproterone Acetate, Ethinyl EstradiolDiane-35, Dianette
How Cyproterone Acetate, Ethinyl Estradiol interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CEstrogens Moderate
Interaction Summary
Vitamin C might increase blood levels of estrogens.
Read the full Vitamin C + Cyproterone Acetate, Ethinyl Estradiol interactionDacarbazineDTIC-Dome
How Dacarbazine interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAlkylating Agents Moderate
Interaction Summary
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Read the full Vitamin C + Dacarbazine interactionDactinomycinCosmegan, Cosmegen
How Dactinomycin interacts with Sustained Release Vitamin C 500 mg — through 1 ingredient. Tap an ingredient for the detail:
Vitamin CAntitumor Antibiotics Moderate
Interaction Summary
Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
Read the full Vitamin C + Dactinomycin interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Sustained Release Vitamin C 500 mg 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 Sustained Release Vitamin C 500 mg, from the product label.
Bronson Laboratories
- Name
- Bronson Laboratories
- City
- Lindon
- State
- UT
- ZipCode
- 84042
Sustained Release Vitamin C 500 mg by Bronson Laboratories: Common Questions
Does Sustained Release Vitamin C 500 mg by Bronson Laboratories interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Will this vitamin C supplement interfere with my birth control?
Is 500 mg of vitamin C safe to take every day?
Can I take this if I'm pregnant or breastfeeding?
Does vitamin C actually prevent colds?
What's the difference between regular and sustained-release vitamin C?
Can high-dose vitamin C cause kidney stones?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Sustained Release Vitamin C 500 mg is safe with your meds?
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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 Sustained Release Vitamin C 500 mg’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Sustained Release Vitamin C 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.
- 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
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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.
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