Interactions on record — worth a quick check against your medications. Based on 5 of 6 ingredients. Check your meds →
Dietary supplement

Daily C-Protect Nutrient Booster Powder Ingredients & Drug Interactions

by MegaFood

Daily C-Protect Nutrient Booster Powder label
See full label image
Powder Category: Botanical With Nutrients
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Daily C-Protect Nutrient Booster Powder against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

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

The interaction bottom line Most serious interaction: Moderate

Daily C-Protect Nutrient Booster Powder is a dietary supplement by MegaFood with 6 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 1,059 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are organic Schisandra, organic Cranberry, organic Astragalus. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Daily C-Protect Nutrient Booster Powder by MegaFood

Ask about any prescription or over-the-counter medication and we check it for interactions with Daily C-Protect Nutrient Booster Powder by MegaFood — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Daily C-Protect Nutrient Booster Powder by MegaFood

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 23, 2026

What’s inside

Partial disclosure
Ingredient Transparency · database check
Partial

Most active ingredients list an amount, but at least one is hidden in a blend or missing.

Why this rating?
  • The label discloses an exact amount for 3 of its 6 active ingredients.
  • “Fruit Phenolic Blend” is a proprietary blend — the label gives one combined amount (755 mg) without saying how much of each component you get.
  • “Immune-Balancing Blend” is a proprietary blend — the label gives one combined amount (375 mg) without saying how much of each component you get.

Daily C-Protect Nutrient Booster Powder contains 6 active ingredients: organic blueberry, organic astragalus, vitamin C, organic cranberry, fruit phenolic blend, and organic schisandra. The product also includes organic whole orange and an immune-balancing blend, though we hold no interaction data for the orange.

There are no inactive ingredients (fillers, binders, or capsule materials) listed on the label. These ingredients are meant to work together as a nutrient booster—blueberry and cranberry provide antioxidants from whole fruit, vitamin C supports immune function and collagen, astragalus and schisandra are traditional botanicals used in herbal medicine, and the phenolic and immune-balancing blends round out the formula.

Does it work?

Strong 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

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Vitamin C deficiency — rated "Effective" (Vitamin C) (Natural Medicines).
  • On file: Anemia of chronic disease — rated "Possibly Effective" (Vitamin C) (Natural Medicines).
  • On file: Atrial fibrillation — rated "Possibly Effective" (Vitamin C) (Natural Medicines).
  • On file: Cataracts — rated "Possibly Effective" (Vitamin C) (Natural Medicines).
  • On file: Exercise-induced respiratory infections — rated "Possibly Effective" (Vitamin C) (Natural Medicines).

The evidence for what this powder actually does varies widely by ingredient and health goal. Vitamin C is rated Effective for preventing vitamin C deficiency and Possibly Effective for anemia of chronic disease, cataracts, and exercise-related respiratory infections.

Cranberry is Possibly Effective for urinary tract infections (UTIs). For the other ingredients—blueberry, astragalus, and schisandra—the evidence we hold shows Insufficient Reliable Evidence to Rate them for the conditions they're traditionally used for, including cognitive decline, anxiety, athletic performance, and various chronic conditions.

The phenolic and immune-balancing blends have no effectiveness ratings on file.

The evidence, ingredient by ingredient Vitamin C Blueberry Cranberry Astragalus Schisandra

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Overall, these ingredients are generally well tolerated when used as foods or short-term supplements in healthy adults, though individual ingredient data vary. Blueberry is generally well tolerated; freeze-dried forms may cause constipation, diarrhea, nausea, or vomiting—in one trial, 26% of people taking 50 grams daily dropped out in the first week due to gastrointestinal upset.

Vitamin C is well tolerated at normal doses, but doses above 2 grams daily can cause abdominal cramps, diarrhea, heartburn, or nausea, and very high doses carry rare risks including kidney damage. Astragalus, cranberry, and schisandra are generally well tolerated short-term, though schisandra may cause decreased appetite, heartburn, stomach upset, or skin reactions.

Cranberry in large amounts (3–4 liters of juice daily) can cause gastrointestinal upset and diarrhea. For pregnancy: Blueberry and cranberry are rated Likely Safe.

Vitamin C in normal amounts is Likely Safe, but high-dose supplements are Possibly Unsafe—stick to prenatal-vitamin amounts. Astragalus should be avoided in pregnancy due to insufficient safety data.

Schisandra is rated Possibly Unsafe in pregnancy and should be avoided. For breastfeeding: Blueberry and cranberry are rated Likely Safe.

Vitamin C in recommended amounts is safe, but high-dose supplements should be avoided. Astragalus and schisandra both lack sufficient safety data and should be avoided while breastfeeding.

Speak with your own doctor or pharmacist about whether this product fits your pregnancy or breastfeeding situation.

Side effects, ingredient by ingredient Vitamin C Blueberry Cranberry Astragalus Schisandra

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?
  • 5 of the 5 matched ingredients can interact with medications — Schisandra, Cranberry, Astragalus, Vitamin C, Blueberry.
  • 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: 1,060 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 starting this product, check with your own doctor or pharmacist if you take any of the following: blood thinners like warfarin (schisandra and vitamin C may reduce effectiveness; cranberry may increase it); immunosuppressants or tacrolimus (schisandra and astragalus may increase levels dangerously); heart or statin medications that are CYP3A4 substrates like atorvastatin or nifedipine (cranberry and schisandra may raise levels); diabetes drugs (blueberry and astragalus may lower blood sugar further); chemotherapy drugs like cyclophosphamide or doxorubicin (astragalus may interfere; vitamin C antioxidant effects may reduce effectiveness); antipsychotics or anti-anxiety drugs; lithium; or levothyroxine (thyroid medication).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glancePartially disclosed formula with strong clinical evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

Daily C-Protect is a multi-ingredient nutrient powder best suited for someone looking to add antioxidants and traditional immune-support botanicals to their routine—and who does not take blood thinners, heart medications, immunosuppressants, diabetes drugs, or chemotherapy. If you're on any regular medication or considering this product during pregnancy or breastfeeding, talk it over with your own doctor or pharmacist first, since the interactions and safety data here are significant.

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

Assessment coverage: 5 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated May 19, 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

At a glance

General information

Key facts about Daily C-Protect Nutrient Booster Powder, straight from the product label.

Brand MegaFood
Barcode (UPC) 051494601372
Net contents 63.9 Gram(s); 2.25 Ounce(s)
Market status On market
Date entered into DSLD May 19, 2022
DSLD ID 265187
Product type Botanical With Nutrients
Supplement form Powder
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Daily C-Protect Nutrient Booster Powder by MegaFood, 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:
2.13 Gram(s)
Maximum serving Sizes:
2.13 Gram(s)
Servings per container
30
UPC/BARCODE
051494601372
IngredientAmount% DV
organic Blueberry0 NP--
organic Astragalus200 mg--
Vitamin C250 mg278%
organic Cranberry0 NP--
Fruit Phenolic Blend755 mg--
organic whole Orange0 NP--
Immune-Balancing Blend375 mg--
organic Schisandra175 mg--

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.
Seals/Symbols

Certified B Corporation Non GMO Project Verified nongmoproject.org Glyphosate Residue Free detoxproject.org Tested 125+ Pesticides & Herbicides NSF Certified Gluten-free V Certified Vegan Vegan.org OK (Kosher)

Formula

OK (Kosher)

with Blueberries, Cranberries & Whole Oranges

Daily C-Protect Nutrient Booster Powder contains FoodState Vitamin C, organic blueberries and organic cranberries to provide phytonutrients which function as powerful antioxidants. Organic astragalus and organic schisandra berry herbs are included to support your natural immune defenses. This MegaFood product is made with real food, carefully selected herbs, and added nutrients. Each vitamin is paired with an ideal whole food using our unique process to deliver guaranteed potency and the benefit of health-promoting compounds present in the whole food itself.

Formulation

Certified vegan Vegan.org

Non GMO project verified nongmoproject.org Residue free Glyphosate detoxproject.org Tested 125+ Pesticides & herbicides NSF Certified Gluten-free Dairy free Soy free

Daily C-Protect is bursting with real fruit flavor, so it may intensify the flavor of any beverage you add it to.

Like all of our Boosters, Daily C-Protect contains no added sugar, sweeteners, flavorings, preservatives or fillers.

Brand IP Statement(s)

MegaFood Fresh From Farm to Powder

FDA Statement of Identity

Unsweetened Powder Dietary Supplement

General Statements

30 Scoops 30 servings

See how they're made at megafood.com/showme. Satisfaction guaranteed or your money back. Meet Our Farmers We believe that the most nutritious food comes from healthy soils and valued farmers. Our goal is to work with farmers who share our commitment to organic and regenerative agriculture. megafood.com/farmers

Please Recycle

To learn about our seals, please visit megafood.com/standards.

Suggested/Recommended/Usage/Directions

Suggested Use: Adults, add one level scoop to 6-8 ounces of your favorite smoothie, shake or juice, blend well and enjoy.

Precautions

If pregnant, nursing, or you have a health condition, consult your healthcare practitioner before taking this product.

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.

Storage

Keep lid tightly sealed and once open, consume within 3 months.

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

See for yourself

Daily C-Protect Nutrient Booster Powder by MegaFood label

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

Daily C-Protect Nutrient Booster Powder label

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

View the full label (PDF)
What’s inside

The Ingredients in Daily C-Protect Nutrient Booster Powder by MegaFood

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size2.13 Gram(s) Dosage formPowder Servings per container30 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: organic Orange

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

Fruit Phenolic Blend

755 mg per serving

Immune-Balancing Blend

375 mg per serving
Interaction report

Daily C-Protect Nutrient Booster Powder by MegaFood Drug Interactions

Want to check YOUR meds against Daily C-Protect Nutrient Booster Powder?

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

 Go to the checker
1,059Drugs
1,005 Moderate 54 Minor

Ingredients driving the most interactions

organic Schisandra 803
organic Cranberry 712
organic Astragalus 208
Vitamin C 207
organic Blueberry 88

Individual Drug Interactions

The ingredients in Daily C-Protect Nutrient Booster Powder interact with 1,059 drugs. Click any drug to see the details.

5 of the 6 ingredients in Daily C-Protect Nutrient Booster Powder interact with drugs. Each result below shows which ingredient is responsible. organic Schisandra organic Cranberry organic Astragalus Vitamin C organic Blueberry

Each ingredient & the kinds of drugs it affects

For each ingredient in Daily C-Protect Nutrient Booster Powder 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.

organic Schisandra12 drug types · 803 drugs

Cyclophosphamide

Theoretically, schisandra might increase the levels and clinical effects of cyclophosphamide.
In vitro research shows that schisandra increases the concentration of cyclophosphamide, likely through inhibition of cytochrome P450 3A4. After multiple doses of the schisandra constituents schisandrin A and schisantherin A, the maximum concentration of cyclophosphamide was increased by 7% and 75%, respectively, while the overall exposure to cyclophosphamide was increased by 29% and 301%, respectively.

Likelihood Probable Evidence D
Cyclosporine (Neoral, Sandimmune)

Schisandra can increase the levels and clinical effects of cyclosporine.
A small observational study in children with aplastic anemia found that taking schisandra with cyclosporine increased cyclosporine trough levels by 93% without increasing the risk of adverse events. However, the dose of cyclosporine was reduced in 9% of children to maintain appropriate cyclosporine blood concentrations.

Likelihood Probable Evidence B
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, schisandra might increase the levels and clinical effects of CYP2C19 substrates.
In vitro research shows that schisandra inhibits CYP2C19, and animal research shows that schisandra increases the concentration of voriconazole, a CYP2C19 substrate. Theoretically, schisandra may also inhibit the metabolism of other CYP2C19 substrates. This effect has not been reported in humans.

Likelihood Probable Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, schisandra might decrease the levels and clinical effects of CYP2C9 substrates.
In vitro and animal research suggests that schisandra induces CYP2C9 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Schisandra can increase the levels and clinical effects of drugs metabolized by CYP3A4.
Most clinical and laboratory research shows that schisandra, administered either as a single dose or up to twice daily for 14 days, inhibits CYP3A4 and increases the concentration of CYP3A4 substrates such as cyclophosphamide, midazolam, tacrolimus, and talinolol. Although one in vitro and animal study shows that schisandra may induce CYP3A4 metabolism, this effect appears to be overpowered by schisandra's CYP3A4 inhibitory activity and has not been reported in humans.

Likelihood Probable Evidence D
Midazolam (Versed)

Schisandra can increase the levels and clinical effects of midazolam.
A small pharmacokinetic study in healthy adults shows that taking schisandra extract (Hezheng Pharmaceutical Co.) containing deoxyschizandrin 33.75 mg twice daily for 8 days and a single dose of midazolam 15 mg on day 8 increases the overall exposure to midazolam by about 119%, increases the peak plasma level of midazolam by 86%, and decreases midazolam clearance by about 52%. This effect has been attributed to inhibition of CYP3A4 by schisandra.

Likelihood Probable Evidence B
P-Glycoprotein Substrates

Schisandra might increase the levels and clinical effects of P-glycoprotein substrates.
In vitro research shows that schisandra extracts and constituents such as schisandrin B inhibit P-glycoprotein mediated efflux in intestinal cells and in P-glycoprotein over-expressing cell lines. Additionally, a small clinical study shows that schisandra increases the peak concentration and overall exposure to talinolol, a P-glycoprotein probe substrate. Theoretically, schisandra might inhibit the efflux of other P-glycoprotein substrates.

Likelihood Possible Evidence D
Sirolimus (Rapamune)

Schisandra can increase the levels and clinical effects of sirolimus.
A small pharmacokinetic study in healthy volunteers shows that taking 3 capsules of schisandra (Hezheng Pharmaceutical Company) containing a total of 33.75 mg deoxyschizandrin twice daily for 13 days and then taking a single dose of sirolimus 2 mg increases the overall exposure and peak level of sirolimus by two-fold. This effect is thought to be due to inhibition of cytochrome P450 3A4 by schisandra, as well as possible inhibition of the P-glycoprotein drug transporter.

Likelihood Probable Evidence B
Tacrolimus (Prograf)

Schisandra can increase the levels and clinical effects of tacrolimus.
Clinical research in healthy children and adults, transplant patients, and patients with nephrotic syndrome and various rheumatic immunologic disorders shows that taking schisandra with tacrolimus increases tacrolimus peak levels by 183% to 268%, prolongs or delays time to peak tacrolimus concentrations, increases overall exposure to tacrolimus by 126% to 343%, and decreases tacrolimus clearance by 19% to 73%. This effect is thought to be due to inhibition of P-glycoprotein drug transporter and CYP3A4 and CYP3A5 by schisandra. Some clinical and observational studies suggest that schisandra increases tacrolimus levels similarly in both expressors and non-expressors of CYP3A5, while other studies suggest it does so to a greater degree in CYP3A5 expressors than non-expressors. Animal research suggests that the greatest increase in tacrolimus levels occurs when schisandra is taken either concomitantly or up to 2 hours before tacrolimus, and clinical and observational research in humans suggests that schisandra may increase whole blood levels of tacrolimus and decrease clearance of tacrolimus in a dose-dependent manner.

Likelihood Probable Evidence B
Talinolol

Schisandra can increase the levels and clinical effects of talinolol.
A small pharmacokinetic study in healthy volunteers shows that taking schisandra extract 300 mg twice daily for 14 days with a single dose of talinolol 100 mg on day 14 increases the peak talinolol level by 51% and the overall exposure to talinolol by 47%. This effect is thought to be due to the possible inhibition of cytochrome P450 3A4 and P-glycoprotein by schisandra. tly.

Likelihood Probable Evidence B
Voriconazole (Vfend)

Theoretically, schisandra might increase the levels and clinical effects of voriconazole.
Animal research shows that oral schisandra given daily for 1 or 14 days increases levels of intravenously administered voriconazole, a cytochrome P450 (CYP) 2C19 substrate. This effect is thought to be due to inhibition of CYP2C19 by schisandra. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, schisandra might decrease the levels and clinical effects of warfarin.
Animal research suggests that oral schisandra extract, given daily for 6 days, reduces levels of intravenously administered warfarin. This effect might be due to the induction of cytochrome P450 (CYP) 2C9 metabolism by schisandra. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
organic Schisandra full monograph & interactions

organic Cranberry6 drug types · 712 drugs

Atorvastatin (Lipitor)

Theoretically, cranberry might increase levels and adverse effects of atorvastatin.
In one case report, a patient taking atorvastatin experienced upper back pain, rhabdomyolysis, and abnormal liver function after drinking cranberry juice 16 ounces daily for 2 weeks. Theoretically, this may have been caused by inhibition of cytochrome P450 3A4 (CYP3A4) enzymes by cranberry juice, as atorvastatin is a CYP3A4 substrate. Creatinine kinase and liver enzymes normalized within 2 weeks of stopping cranberry juice. Patients taking atorvastatin should avoid large quantities of cranberry juice.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, cranberry might increase the levels and adverse effects of CYP3A4 substrates.
A case of upper back pain, rhabdomyolysis, and abnormal liver function has been reported for a patient taking atorvastatin, a CYP3A4 substrate, in combination with cranberry juice 16 ounces daily for 2 weeks. Creatinine kinase and liver enzymes normalized within 2 weeks of stopping cranberry juice. Also, animal research suggests that cranberry juice, administered intraduodenally 30 minutes prior to nifedipine, a CYP3A4 substrate, inhibits nifedipine metabolism and increases the area under the concentration-time curve by 1.6-fold compared to control.

Likelihood Possible Evidence D
Nifedipine (Procardia)

Theoretically, cranberry might increase the levels and adverse effects of nifedipine.
Animal research suggests that cranberry juice, administered intraduodenally 30 minutes prior to nifedipine treatment, inhibits nifedipine metabolism and increases the area under the concentration-time curve by 1.6-fold compared to control. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, cranberry might increase the levels and adverse effects of warfarin. However, research is conflicting.
There is contradictory evidence about the effect of cranberry juice on warfarin. Case reports have linked cranberry juice consumption to increases in the international normalized ratio (INR) in patients taking warfarin, resulting in severe spontaneous bleeding and excessive postoperative bleeding. Daily consumption of cranberry sauce for one week has also been linked to an increase in INR in one case report. In a small study in healthy young males, taking a high dose of 3 grams of cranberry juice concentrate capsules, equivalent to 57 grams of fruit daily, for 2 weeks produced a 30% increase in the area under the INR-time curve after a single 25-mg dose of warfarin. However, 3 very small clinical studies in patients stabilized on warfarin reported that cranberry juice 250 mL once or twice daily for 7 days (27% cranberry juice or pure cranberry juice) or 240 mL once daily for 14 days does not significantly increase INR or affect plasma warfarin levels. The reasons for these discrepant findings are unclear. It is possible that the form and dose of cranberry may play a role, as cranberry extracts and juices contain different constituents. Additionally, an in vitro study evaluating 5 different cranberry juices found varying effects, with only a cranberry concentrate, and not diluted cranberry juices, inhibiting CYP2C9. However, this concentrate did not inhibit CYP2C9 activity in humans.

Likelihood Possible Evidence B
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, cranberry might increase the levels and adverse effects of CYP2C9 substrates. However, research is conflicting.
There is contradictory evidence about the effect of cranberry on CYP2C9 enzymes. In vitro evidence suggests that flavonoids in cranberry inhibit CYP2C9 enzymes. However, clinical research shows that cranberry juice does not significantly affect the levels, metabolism, or elimination of the CYP2C9 substrates flurbiprofen or diclofenac. Also, in patients stabilized on warfarin, drinking cranberry juice 250 mL daily for 7 days does not significantly increase the anticoagulant activity of warfarin, a CYP2C9 substrate. Additional pharmacokinetic research shows that cranberry juice does not increase peak plasma concentrations or area under the concentration-time curve of warfarin.

Likelihood Unlikely Evidence B
Diclofenac (Voltaren, Others)

Theoretically, cranberry might modestly increase the levels and adverse effects of diclofenac.
In vitro evidence suggests that cranberry juice inhibits diclofenac metabolism by human liver microsomes. However, drinking cranberry juice does not seem to affect diclofenac metabolism in humans.

Likelihood Unlikely Evidence B
organic Cranberry full monograph & interactions

organic Astragalus4 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
organic Astragalus full monograph & interactions

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
Vitamin C full monograph & interactions

organic Blueberry3 drug types · 88 drugs

Antidiabetes Drugs

Theoretically, blueberries or blueberry leaf extracts might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal and in vitro research suggests that blueberry and/or blueberry leaf extracts can lower blood glucose levels.

Likelihood Unlikely Evidence D
Buspirone (Buspar)

Theoretically, blueberry juice might increase blood levels of buspirone.
In vitro research shows that blueberry juice can inhibit the metabolism of buspirone, possibly by inhibiting cytochrome P450 3A (CYP3A) enzymes. However, pharmacokinetic research in humans shows that drinking 300 mL of blueberry juice 30 minutes before taking buspirone hydrochloride 10 mg does not significantly affect the concentration or clearance of buspirone.

Likelihood Unlikely Evidence B
Flurbiprofen (Ansaid, Others)

Theoretically, blueberry juice might increase blood levels of flurbiprofen.
In vitro research shows that blueberry juice can inhibit the metabolism of flurbiprofen, possibly by inhibiting cytochrome P450 2C9 (CYP2C9) enzymes. However, pharmacokinetic research in humans shows that drinking 300 mL of blueberry juice 30 minutes before taking flurbiprofen 100 mg does not significantly affect the concentration or clearance of flurbiprofen.

Likelihood Unlikely Evidence B
organic Blueberry full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Daily C-Protect Nutrient Booster Powder, from the product label.

MegaFood

See all MegaFood products
Name
MegaFood
Street Address
PO Box 5244
City
Manchester
State
NH
ZipCode
03108
Phone Number
800.848.2542
Web Address
megafood.com
Pharmacist Counseling Corner

Daily C-Protect Nutrient Booster Powder by MegaFood: Common Questions

Does Daily C-Protect Nutrient Booster Powder by MegaFood interact with any medications?
Yes. Based on its ingredients, Daily C-Protect Nutrient Booster Powder has a known interaction with 1,059 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Daily C-Protect Nutrient Booster Powder contains 6 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.
Can I take this if I'm pregnant?
Blueberry and cranberry are rated Likely Safe in pregnancy. Vitamin C in prenatal-vitamin amounts is fine, but avoid high-dose supplements. However, astragalus and schisandra should be avoided in pregnancy due to insufficient safety data. Talk with your own doctor or pharmacist before taking this product during pregnancy, since it contains astragalus and schisandra.
Can I take this while breastfeeding?
Blueberry and cranberry are rated Likely Safe. Vitamin C at recommended dietary amounts is safe. However, astragalus and schisandra lack reliable safety data for breastfeeding and should be avoided. Check with your own healthcare provider about whether this product is right for you while nursing.
What's schisandra, and what does it do?
Schisandra is a traditional botanical used in herbal medicine, but the evidence we hold shows Insufficient Reliable Evidence to Rate it for the conditions it's commonly used for—like asthma, athletic performance, or hepatitis. While it's generally well tolerated short-term in healthy adults, it does have significant drug interactions and should be avoided in pregnancy and while breastfeeding.
Does cranberry in this powder actually help with UTIs?
Cranberry is rated Possibly Effective for urinary tract infections (UTIs), so there is some evidence it may help. However, it is not a substitute for medical treatment of an active infection, so if you have a UTI, see your doctor.
Will freeze-dried blueberries in this powder cause digestive issues like the ones I've heard about?
Freeze-dried blueberries can cause constipation, diarrhea, nausea, or vomiting in some people—in one trial, a significant number of participants dropped out due to gastrointestinal upset. This powder's formulation and dose may differ, so start with the recommended serving and see how you tolerate it. If you experience digestive symptoms, stop and talk to your pharmacist.
Is there a lot of vitamin C in this powder, and could it cause side effects?
The label does not specify the exact amount of vitamin C. Vitamin C at normal supplement doses is generally well tolerated, but doses above 2 grams daily can cause abdominal cramps, diarrhea, heartburn, or nausea. Check the nutrition facts panel for the exact dose, and if you're prone to kidney stones or take warfarin, discuss this with your own pharmacist.

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.

Daily C-Protect Nutrient Booster Powder label
Go deeper

The Full Monographs Behind Daily C-Protect Nutrient Booster Powder’s Ingredients

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

Herb & supplement monograph

Vitamin C

Interacts with 207 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 immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

Blueberry

Interacts with 88 drugs

Blueberries are a nutritious fruit rich in antioxidants called anthocyanins, and eating them as part of a balanced diet is healthy and safe for most people. Concentrated supplements are mark...

Read the full Blueberry monograph → Herb & supplement monograph

Cranberry

Interacts with 712 drugs

Cranberry is best known for helping to prevent repeated urinary tract infections (UTIs) in some people, and the evidence here is moderate but mixed. It is not a reliable treatment for an act...

Read the full Cranberry monograph → Herb & supplement monograph

Astragalus

Interacts with 208 drugs

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 early studies are interesting, strong h...

Read the full Astragalus monograph → Herb & supplement monograph

Schisandra

Interacts with 803 drugs

Schisandra is a traditional Chinese medicine berry used as an adaptogen for stress, fatigue, and liver support. Human evidence is limited and most claims are not well proven, but it appears...

Read the full Schisandra monograph →
Sources

Sources & How We Checked

Daily C-Protect Nutrient Booster Powder'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 130 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.

Blueberry 7 references
  1. Cignarella A, Nastasi M, Cavalli E, Puglisi L. Novel lipid-lowering properties of Vaccinium myrtillus L. leaves, a traditional antidiabetic treatment, in several models of rat dyslipidaemia: a comparison with ciprofibrate. Thromb Res 1996;84:311-22. PubMed
  2. Wang SY, Lin HS. Antioxidant activity in fruits and leaves of blackberry, raspberry, and strawberry varies with cultivar and developmental stage. J Agric Food Chem 2000;48:140-6.. PubMed
  3. Martineau, L. C., Couture, A., Spoor, D., Benhaddou-Andaloussi, A., Harris, C., Meddah, B., Leduc, C., Burt, A., Vuong, T., Mai, Le P., Prentki, M., Bennett, S. A., Arnason, J. T., and Haddad, P. S. Anti-diabetic properties of the Canadian lowbush bluebe
  4. Vuong, T., Martineau, L. C., Ramassamy, C., Matar, C., and Haddad, P. S. Fermented Canadian lowbush blueberry juice stimulates glucose uptake and AMP-activated protein kinase in insulin-sensitive cultured muscle cells and adipocytes. Can J Physiol Pharma
  5. Hanley MJ, Masse G, Harmatz JS, Cancalon PF, Dolnikowski GG, Court MH, Greenblatt DJ. Effect of blueberry juice on clearance of buspirone and flurbiprofen in human volunteers. Br J Clin Pharmacol. 2013 Apr;75(4):1041-52. PubMed
  6. Basu A, Du M, Leyva MJ, et al. Blueberries decrease cardiovascular risk factors in obese men and women with metabolic syndrome. J Nutr 2010;140(9):1582-7. PubMed
  7. Basu A, Feng D, Planinic P, Ebersole JL, Lyons TJ, Alexander JM. Dietary blueberry and soluble fiber supplementation reduces risk of gestational diabetes in women with obesity in a randomized controlled trial. J Nutr 2021;151(5):1128-38. PubMed

See these in context on the Blueberry monograph →

Astragalus 13 references
  1. Upton R, ed. Astragalus Root: Analytical, quality control, and therapeutic monograph. Santa Cruz, CA: American Herbal Pharmacopoeia. 1999:1-25.
  2. Khoo KS, Ang PT. Extract of astragalus membranaceus and ligustrum lucidum does not prevent cyclophosphamide-induced myelosuppression. Singapore Med J 1995;36:387-90.
  3. Chu DT, Wong WL, Mavligit GM. Immunotherapy with Chinese medicinal herbs. II. Reversal of cyclophosphamide-induced immune suppression by administration of fractionated Astragalus membranaceus in vivo. J Clin Lab Immunol 1988;25:125-9.
  4. Sun Y, Hersh EM, Lee SL, et al. Preliminary observations on the effects of the Chinese medicinal herbs Astragalus membranaceus and Ligustrum lucidum on lymphocyte blastogenic responses. J Biol Response Mod 1983;2:227-37..
  5. Ma J, Peng A, Lin S. Mechanisms of the therapeutic effect of astragalus membranaceus on sodium and water retention in experimental heart failure. Chin Med J (Engl) 1998;111:17-23.
  6. Matkovic Z, Zivkovic V, Korica M, et al. Efficacy and safety of Astragalus membranaceus in the treatment of patients with seasonal allergic rhinitis. Phytother Res 2010;24:175-81.
  7. Zhang, J. G., Yang, N., He, H., Wei, G. H., Gao, D. S., Wang, X. L., Wang, X. Z., and Song, G. Y. [Effect of Astragalus injection on plasma levels of apoptosis-related factors in aged patients with chronic heart failure.]. Chin J Integr.Med 2005;11(3):18 PubMed
  8. Chen, H. W., Lin, I. H., Chen, Y. J., Chang, K. H., Wu, M. H., Su, W. H., Huang, G. C., and Lai, Y. L. A novel infusible botanically-derived drug, PG2, for cancer-related fatigue: a phase II double-blind, randomized placebo-controlled study. Clin Invest PubMed
  9. Tian H, Lu J, He H, et al.The effect of Astragalus as an adjuvant treatment in type 2 diabetes mellitus: A (preliminary) meta-analysis. J Ethnopharmacol. 2016;191:206-215. doi: 10.1016/j.jep.2016.05.062. PubMed
  10. Hong KF, Liu PY, Zhang W, Gui DK, Xu YH. The Efficacy and Safety of Astragalus as an Adjuvant Treatment for Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis. J Integr Complement Med 2023. PubMed
  11. Chan KW, Kwong ASK, Tsui PN, et al. Add-on astragalus in type 2 diabetes and chronic kidney disease: A multi-center, assessor-blind, randomized controlled trial. Phytomedicine 2024;130:155457. PubMed
  12. Han X, Yu T, Chen X, Du Z, Yu M, Xiong J. Effect of Astragalus membranaceus on left ventricular remodeling in HFrEF: a systematic review and meta-analysis. Front Pharmacol 2024;15:1345797. PubMed
  13. Jing P, Hongzheng H, Zhenqi WU, Meijuan Z, Zuojing LI, Gang C. Long-term efficacy and safety of Huangqi ()-based Traditional Chinese Medicine in diabetic peripheral neuropathy: a Meta-analysis of randomized controlled trials. J Tradit Chin Med 2024;44(2):

See these in context on the Astragalus monograph →

Vitamin C 51 references
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  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
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
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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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  15. 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
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  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
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  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
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  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
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  33. 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.
  34. 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
  35. 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.
  36. 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.
  37. 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
  38. 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
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See these in context on the Vitamin C monograph →

Cranberry 33 references
  1. Anon. Possible interaction between warfarin and cranberry juice. Current Problems in Pharmacovigilance 2003;29:8. PubMed
  2. Greenblatt DJ, von Moltke LL, Perloff ES, et al. Interaction of flurbiprofen with cranberry juice, grape juice, tea, and fluconazole: in vitro and clinical studies. Clin Pharmacol Ther 2006;79:125-33. PubMed
  3. Hodek P, Trefil P, Stiborova M. Flavonoids-potent and versatile biologically active compounds interacting with cytochromes P450. Chem Biol Interact 2002;139:1-21.. PubMed
  4. Grant P. Warfarin and cranberry juice: An interaction? J Heart Valve Dis 2004;13:25-6.
  5. Suvarna R, Pirmohamed M, Henderson L. Possible interaction between warfarin and cranberry juice. BMJ 2003;327:1454. PubMed
  6. Li Z, Seeram NP, Carpenter CL, et al. Cranberry does not affect prothrombin time in male subjects on warfarin. J Am Diet Assoc 2006;106:2057-61. PubMed
  7. Lilja JJ, Backman JT, Neuvonen PJ. Effects of daily ingestion of cranberry juice on the pharmacokinetics of warfarin, tizanidine, and midazolam - probes of CYP2C9, CYP1A2 and CYP3A4. Clin Pharmacol The 2007:81:833-9. PubMed
  8. Wing DA, Rumney PJ, Preslicka CW, Chung JH. Daily cranberry juice for the prevention of asymptomatic bacteriuria in pregnancy: a randomized, controlled pilot study. J Urol 2008;180:1367-72. PubMed
  9. Mohammed Abdul MI, Jiang X, Williams KM, et al. Pharmacodynamic interaction of warfarin with cranberry but not with garlic in healthy subjects. Br J Pharmacol 2008;154:1691-700. PubMed
  10. McMurdo MET, Argo I, Phillips G, et al. Cranberry or trimethoprim for the prevention of recurrently urinary tract infections? A randomized controlled trial in older women. J Antimicrob Chemother 2009;63:389-95.
  11. Mergenhagen KA, Sherman O. Elevated International Normalized Ratio after concurrent ingestion of cranberry sauce and warfarin. Am J Health-Syst Pharm 2008;65:2113-6. PubMed
  12. Ansell J, McDonough M, Zhao Y, et al. The absence of an interaction between warfarin and cranberry juice: a randomized, double-blind trial. J Clin Pharmacol 2009;49:824-30. PubMed
  13. Haber SL, Cauthon KA, Raney EC. Cranberry and warfarin interaction: a case report and review of the literature. Consult Pharm 2012;27:58-65. PubMed
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  17. Patel, D. A., Gillespie, B., Sobel, J. D., Leaman, D., Nyirjesy, P., Weitz, M. V., and Foxman, B. Risk factors for recurrent vulvovaginal candidiasis in women receiving maintenance antifungal therapy: results of a prospective cohort study. Am J Obstet.Gy PubMed
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  20. McMurdo, M. E., Bissett, L. Y., Price, R. J., Phillips, G., and Crombie, I. K. Does ingestion of cranberry juice reduce symptomatic urinary tract infections in older people in hospital? A double-blind, placebo-controlled trial. Age Ageing 2005;34(3):256- PubMed
  21. Sylvan, L. and Justice, N. P. Possible interaction between warfarin and cranberry juice. Am Fam.Physician 9-15-2005;72(6):1000.
  22. Niklasson, A. and Andren, L. [Interaction between Waran and cranberry juice]. Lakartidningen 3-15-2006;103(11):853-854.
  23. Rindone, J. P. and Murphy, T. W. Warfarin-cranberry juice interaction resulting in profound hypoprothrombinemia and bleeding. Am J Ther 2006;13(3):283-284. PubMed
  24. Uesawa, Y. and Mohri, K. Effects of cranberry juice on nifedipine pharmacokinetics in rats. J Pharm Pharmacol 2006;58(8):1067-1072. PubMed
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See these in context on the Cranberry monograph →

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See these in context on the Schisandra monograph →

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

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