Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Astragalus, Vitamin C & Elderberry Ingredients & Drug Interactions

by Vitamin World

Capsule Category: Botanical With Nutrients
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Astragalus, Vitamin C & Elderberry is a dietary supplement by Vitamin World with 3 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 413 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Astragalus Extract, Vitamin C, Elderberry extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Astragalus, Vitamin C & Elderberry by Vitamin World

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

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains three active ingredients: Vitamin C, Astragalus Extract, and Elderberry Extract. Vitamin C is an essential nutrient and antioxidant that supports immune function and collagen formation.

Astragalus Extract, a traditional herbal ingredient, is included for immune support. Elderberry Extract comes from the ripe fruit of the elder plant and is used similarly for immune and respiratory support.

The capsule itself is made from gelatin and vegetable cellulose, with dicalcium phosphate as a filler — these are inactive ingredients that help form and fill the capsule.

Does it work?

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

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: immune support and respiratory health.
  • We looked for evidence on: Acute bronchitis, Asthma, Exercise-induced respiratory infections, common cold, influenza, upper respiratory infections.
  • The strongest evidence on file: Vitamin C is rated "Possibly Effective" for Exercise-induced respiratory infections (Natural Medicines).
  • Also on file: Vitamin C is rated "Possibly Ineffective" for Acute bronchitis.
  • Also on file: Astragalus is rated "Insufficient Reliable Evidence To Rate" for Asthma.

The evidence for these ingredients is mixed. Vitamin C is effective for preventing vitamin C deficiency and has possibly effective evidence for anemia, atrial fibrillation, cataracts, and exercise-induced respiratory infections — though strength varies.

For Astragalus Extract and Elderberry Extract, the data we hold does not establish reliable evidence for any specific use: hay fever, heart conditions, fatigue, respiratory infections, and other conditions listed all have insufficient evidence to rate them. That doesn't mean they don't work — it means the research available to us hasn't confirmed their effectiveness yet.

The evidence, ingredient by ingredient Vitamin C Astragalus Elderberry

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

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

Why this rating?
  • We hold adverse-effect (side-effect) data for 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin C is generally well tolerated at normal dietary and supplement doses. At very high doses above 2 grams daily, side effects can occur: abdominal cramps, heartburn, nausea, vomiting, diarrhea, and headache are most common.

Kidney stones have been reported in people prone to them. The product is likely safe in pregnancy at normal amounts (like from food or prenatal vitamins), but high-dose supplements in pregnancy should only be used if advised by your doctor.

Astragalus Extract is generally well tolerated short-term in healthy adults, but human safety data is limited. It should be avoided during pregnancy and breastfeeding due to insufficient safety information.

Elderberry Extract from properly cooked ripe fruit is well tolerated; raw or unripe berries and plant parts can cause nausea, vomiting, diarrhea, dizziness, and weakness. Elderberry should be avoided in pregnancy and breastfeeding — there isn't enough reliable safety data.

One rare case of autoimmune hepatitis has been reported after long-term elderberry use in someone with underlying autoimmune disease.

Side effects, ingredient by ingredient Vitamin C Astragalus Elderberry

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

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

Why this rating?
  • 3 of the 3 matched ingredients can interact with medications — Elderberry, Astragalus, Vitamin C.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; diabetes medications; lithium.
  • For scale: 413 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your doctor or pharmacist if you take estrogen-based birth control or hormone replacement therapy (Vitamin C may raise estrogen levels), blood thinners like warfarin (Vitamin C may reduce their effectiveness), levothyroxine or other thyroid medications (Vitamin C may increase absorption and affect your dose), immunosuppressants (Astragalus and Elderberry may interfere), lithium (Astragalus may raise levels), blood sugar medications (Astragalus may increase low blood sugar risk), chemotherapy drugs including alkylating agents or antitumor antibiotics (Vitamin C and Astragalus may reduce their activity), or pazopanib cancer medication (Elderberry may increase risk of side effects). These interactions span 413 individual medications overall.

Check your own medication Run your meds through the checker above

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.

This product is worth considering if you want immune support from these three ingredients and don't take medications that interact with them — especially estrogen-based contraceptives or hormone therapy, blood thinners, thyroid medication, immunosuppressants, or cancer drugs. If you take any prescription medication or have diabetes, a heart condition, kidney disease, or autoimmune disease, talk with your doctor or pharmacist before starting.

They can review your specific situation and confirm whether this combination is right for you.

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

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 25, 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

At a glance

General information

Key facts about Astragalus, Vitamin C & Elderberry, straight from the product label.

Brand Vitamin World
Barcode (UPC) 766443520054
Net contents 60 Rapid Release Capsule(s)
Market status On market
Date entered into DSLD Apr 25, 2013
DSLD ID 20966
Product type Botanical With Nutrients
Supplement form Capsule
Dietary claims / uses All Other, Qualified Health, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Astragalus, Vitamin C & Elderberry by Vitamin World, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
UPC/BARCODE
766443520054
IngredientAmount% DV
Vitamin C250 mg417%
Astragalus Extract100 mg--
Elderberry extract40 mg--

Other ingredients: Gelatin, Vegetable Cellulose, Dicalcium Phosphate, Contains <2% of

Tap any ingredient to jump to its full detail below.

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

This product has been developed, manufactured and packaged by Vitamin World. Our world-class facilites allow us to control exactly what goes into each product. It is your assurance that you are getting the highest quality and freshest products. You have our guarantee!

WARNING: If you are pregnant, nursing, taking any medications or have any medical condition, consult your doctor before use.

Discontinue use and consult your doctor if any adverse reactions occur.

Keep out of reach of children.

Do not use if seal under cap is broken or missing.

Seals/Symbols

QA QUALITY ASSURED

Formulation

No Artificial Color, Flavor or Sweetener, No Preservatives, No Sugar, No Starch, No Milk, No Lactose, No Soy, No Gluten, No Wheat, No Yeast, No Fish. Sodium Free.

Storage

Store at room temperature.

Brand IP Statement(s)

(C) 2012 Vitamin World, Inc.

General

PROD. #52005 B52005 00A

General Statements

Get healthy.

SUPERIOR ANTIOXIDANT SUPPORT* Nourishes The Immune System *

This product can support immune health.* It is made of two traditional herbs with essential Vitamin C. Astragalus and Elderberry naturally contain phytonutrients. Astragalus has been used as a traditional herb in Chinese tonics.

FDA Statement of Identity

DIETARY SUPPLEMENT

Suggested/Recommended/Usage/Directions

DIRECTIONS: For adults, take one (1) capsule two times daily, preferably with meals.

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.

See for yourself

Astragalus, Vitamin C & Elderberry by Vitamin World label

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

What’s inside

The Ingredients in Astragalus, Vitamin C & Elderberry by Vitamin World

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

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

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

Vitamin C

Interacts with
207 drugs
250 mg per serving Form: Ascorbic Acid

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 & interactions

Astragalus Extract

Interacts with
208 drugs
100 mg per serving

Astragalus is a root used for centuries in traditional Chinese medicine, mainly to support the immune system and help the body cope with stress. While...

Astragalus Extract monograph & interactions

Elderberry extract

Interacts with
121 drugs
40 mg per serving

Elderberry is a popular herbal supplement, mainly taken to help with colds and flu. Some small studies suggest it may modestly shorten cold or flu sym...

Elderberry extract monograph & interactions

Other (inactive) ingredients: Gelatin, Vegetable Cellulose, Dicalcium Phosphate, Contains <2% of. These complete the product’s ingredient list but are not active constituents.

Interaction report

Astragalus, Vitamin C & Elderberry by Vitamin World Drug Interactions

Want to check YOUR meds against Astragalus, Vitamin C & Elderberry?

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

Go to the checker
413Drugs
307 Moderate 106 Minor

Ingredients driving the most interactions

Vitamin C 207

Each ingredient & the kinds of drugs it affects

For each ingredient in Astragalus, Vitamin C & Elderberry with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Astragalus Extract4 drug types · 208 drugs

Antidiabetes Drugs

Theoretically, taking astragalus with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical research in humans shows that astragalus might have hypoglycemic effects. Theoretically, taking astragalus, especially in combination with other hypoglycemic agents, might increase the risk of hypoglycemia.

Likelihood Probable Evidence A
Cyclophosphamide

Theoretically, astragalus might interfere with cyclophosphamide therapy.
Evidence regarding the effect of astragalus on immunosuppression caused by cyclophosphamide is conflicting. Some animal research suggests that astragalus reverses cyclophosphamide-induced immunosuppression. However, other animal research shows no effect.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, astragalus might interfere with immunosuppressive therapy.
Astragalus seems to stimulate immune function. Theoretically, taking astragalus might decrease the effects of immunosuppressive therapy.

Likelihood Possible Evidence D
Lithium

Theoretically, astragalus might increase levels and adverse effects of lithium.
Animal research suggests that astragalus has diuretic properties. Theoretically, due to this diuretic effect, astragalus might reduce excretion and increase levels of lithium.

Likelihood Probable Evidence D

Vitamin C13 drug types · 207 drugs

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.

Likelihood Possible Evidence D
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.

Likelihood Probable Evidence B
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.

Likelihood Possible Evidence D
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.

Likelihood Probable Evidence B
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.

Likelihood Possible Evidence D
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.

Likelihood Probable Evidence B
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.

Likelihood Probable Evidence B
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.

Likelihood Possible Evidence D
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.

Likelihood Probable Evidence B
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.

Likelihood Possible Evidence B
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.

Likelihood Possible Evidence B
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.

Likelihood Possible Evidence A
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.

Likelihood Possible Evidence B

Elderberry extract2 drug types · 121 drugs

Immunosuppressants

Theoretically, elderberry might interfere with immunosuppressant therapy due to its immunostimulant activity.
Elderberry has immunostimulant activity, increasing the production of cytokines, including interleukin and tumor necrosis factor.

Likelihood Possible Evidence B
Pazopanib (Votrient)

Theoretically, elderberry might interact with pazopanib, potentially increasing the risk of adverse effects.
In one case, a 65-year-old patient taking pazopanib for 4 weeks for soft-tissue sarcoma developed severe nausea, loose stools, and elevated alanine transaminase and aspartate transaminase levels and was diagnosed with grade 3 liver injury. The patient reported taking elderberry supplements for 2 years, dose unspecified, and was also taking a multivitamin and a calcium supplement. The patient's symptoms and liver enzyme levels improved upon discontinuation of pazopanib and all supplements. Pazopanib treatment was re-initiated, at a lower dose, with no further evidence of liver injury. It was unclear in this case report if the elderberry supplements were derived from the berry, the flower, or the combination.

Likelihood Possible Evidence D
The maker

Brand information

Manufacturer and brand details for Astragalus, Vitamin C & Elderberry, from the product label.

Vitamin World

See all Vitamin World products
Name
Vitamin World, Inc.
City
Ronkonkoma
State
NY
ZipCode
11779
Pharmacist Counseling Corner

Astragalus, Vitamin C & Elderberry by Vitamin World: Common Questions

Does Astragalus, Vitamin C & Elderberry by Vitamin World interact with any medications?
Yes. Based on its ingredients, Astragalus, Vitamin C & Elderberry has a known interaction with 413 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Astragalus, Vitamin C & Elderberry contains 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is it safe to take this if I'm pregnant?
Vitamin C is likely safe in pregnancy at normal dietary amounts, but the label will tell you the dose per capsule — avoid high-dose supplements unless your doctor advises it. Astragalus Extract and Elderberry Extract should be avoided in pregnancy due to insufficient safety data. Talk with your doctor or pharmacist about whether this product is right for you during pregnancy.
Is it safe while breastfeeding?
Vitamin C is generally safe at normal doses while breastfeeding. Astragalus Extract and Elderberry Extract should be avoided while breastfeeding — there isn't enough reliable safety information. Discuss with your doctor or pharmacist for personalized advice.
Will this actually help my immune system?
Vitamin C's role in immune function is established, but the evidence we hold doesn't confirm that Astragalus Extract or Elderberry Extract work for specific conditions like colds, flu, or hay fever — the research simply isn't there yet in our data. You may want to discuss realistic expectations with your pharmacist.
What side effects should I watch for?
Vitamin C, especially at higher doses, can cause stomach cramps, heartburn, nausea, vomiting, and diarrhea. Astragalus may cause dizziness or, rarely, palpitations. Elderberry from properly prepared (cooked) extracts is well tolerated — raw berries can cause nausea, vomiting, severe diarrhea, and dizziness. Stop and call your pharmacist or doctor if you notice unusual symptoms.
Does the dose matter for safety?
Yes. Vitamin C side effects are much more likely above 2 grams daily; the label will show you the dose per capsule. The other ingredients' safety in different doses isn't well established in our data, so follow the label instructions and talk with your pharmacist if you're unsure.
What if I take blood pressure or diabetes medications?
Astragalus may theoretically increase the risk of low blood sugar when taken with diabetes medications, so your doctor should know if you're adding it. If you take other medications, use the interaction checker on this page or confirm with your pharmacist before starting.

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

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

Astragalus, Vitamin C & Elderberry label
Sources

Sources & How We Checked

Astragalus, Vitamin C & Elderberry's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

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

The 70 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
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  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. 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
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  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
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  9. 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/.
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  11. 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
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  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. 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
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
  20. Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
  21. Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
  22. 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
  23. 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
  24. 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
  25. 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
  26. Weintraub M, Griner PF. Warfarin and ascorbic acid: lack of evidence for a drug interaction. Toxicol Appl Pharmacol 1974;28:53-6. PubMed
  27. 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
  28. 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
  29. 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
  30. 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
  31. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
  32. 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.
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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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