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

PureWay-C 500 mg Ingredients & Drug Interactions

by Emerald Labs

PureWay-C 500 mg label
See full label image
Capsule Category: Other Combinations
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 PureWay-C 500 mg against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

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

The interaction bottom line Most serious interaction: Moderate

PureWay-C 500 mg is a dietary supplement by Emerald Labs with 2 active ingredients. Its ingredients are commonly taken for diabetic nerve pain (neuropathy), blood sugar support in diabetes, antioxidant support.Based on those ingredients, 387 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are R-Alpha Lipoic Acid, Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against PureWay-C 500 mg by Emerald Labs

Ask about any prescription or over-the-counter medication and we check it for interactions with PureWay-C 500 mg by Emerald Labs — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of PureWay-C 500 mg by Emerald Labs

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 Sep 10, 2026

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 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

PureWay-C 500 mg contains two active ingredients: R-alpha lipoic acid and vitamin C. Alpha-lipoic acid is an antioxidant compound your body naturally produces in small amounts; this form is a stabilized version.

Vitamin C (ascorbic acid) is an essential nutrient you need for immune function, collagen formation, and antioxidant protection. The capsule itself is made from vegetable material.

Does it work?

Leans against
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
Leans against

The strongest graded evidence we hold for the stated purpose leans against a benefit.

Why this rating?
  • The label markets this product for: Support healthy immune response and liver function.
  • We looked for evidence on: Alcohol-related liver disease, Hepatitis C, Immune function, Antioxidant protection, Detoxification support.
  • The closest evidence on file: Alpha-lipoic Acid is rated "Possibly Ineffective" for Alcohol-related liver disease (Natural Medicines).
  • Also on file: Vitamin C is rated "Insufficient Reliable Evidence To Rate" for Hepatitis C.

Vitamin C in this product is rated Effective for vitamin C deficiency and Possibly Effective for several conditions including anemia of chronic disease, atrial fibrillation, cataracts, and respiratory infections from exercise. Alpha-lipoic acid is Possibly Effective for diabetic neuropathy (nerve damage related to diabetes), high cholesterol (hyperlipidemia), and obesity.

Keep in mind that 'Possibly Effective' means there's some evidence but it's not as strong as we'd like, and results vary from person to person.

The evidence, ingredient by ingredient Alpha-lipoic Acid Vitamin C

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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Both ingredients are generally well tolerated at typical doses. The most common side effects from alpha-lipoic acid taken by mouth are headache, heartburn, nausea, and vomiting; skin rash and itching have also been reported.

Vitamin C may cause stomach cramps, heartburn, nausea, vomiting, and diarrhea, especially at doses above 2 grams daily. Kidney stones have been reported in people prone to them, and very high doses can raise your risk of kidney problems.

Alpha-lipoic acid has not been adequately studied in pregnancy or breastfeeding, so the safety data advises against using it during either. For vitamin C, normal dietary amounts and those in prenatal vitamins are considered fine, but high-dose supplements during pregnancy or breastfeeding should be avoided unless your doctor advises otherwise.

Talk with your doctor or pharmacist if you're pregnant or nursing and considering this product.

Side effects, ingredient by ingredient Alpha-lipoic Acid Vitamin C

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?
  • 2 of the 2 matched ingredients can interact with medications — Alpha-lipoic Acid, Vitamin C.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments; diabetes medications.
  • For scale: 387 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, double-check with your doctor or pharmacist if you take blood thinners or antiplatelet drugs (Moderate risk of bleeding); chemotherapy agents (alkylating agents or antitumor antibiotics); thyroid medication; diabetes drugs; oral birth control or hormone replacement therapy; or warfarin. If you take any of these, the interaction data needs to be reviewed for your specific situation.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with graded evidence leaning against its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product may be worth considering if you're interested in supporting cholesterol, blood sugar, or nerve health — but the interactions with blood thinners, chemotherapy, thyroid medication, diabetes drugs, and birth control are real concerns. If you take any prescription medications, run them through the checker on this page before you start.

Talk it over with your doctor or pharmacist to make sure it fits your personal health picture.

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

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 14, 2023.

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 PureWay-C 500 mg, straight from the product label.

Brand Emerald Labs
Barcode (UPC) 743650003556
Net contents 90 Vegetable Cap(s)
Market status On market
Date entered into DSLD Dec 14, 2023
DSLD ID 302735
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), 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 PureWay-C 500 mg by Emerald Labs, 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 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
Servings per container
45
UPC/BARCODE
743650003556
IngredientAmount% DV
R-Alpha Lipoic Acid25 mg--
Vitamin C500 mg833%

Other ingredients: Vegetable Capsule

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.
Formula

Therapeutic dosages of PureWay-C (12-Hour retention vs. standard 4-hours) and superior R-Alpha Lipoic Acid to support: Healthy immune response Optimal liver function

PureWay-C + R-alpha lipoic

General Statements

Emerald Labs is family owned and operated since our beginnings in 1996.

Doctor-formulated

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Brand IP Statement(s)

PureWay-C is a registered trademark of Innovation Laboratories, Inc.

Emerald Labs The additive-free company

Copyright 2021 Emerald Labs, Inc.

Formulation

Enhanced liposomal absorption 12-hour protection Supports healthy immune response & liver function

Clinical potency

Made with Non-GMO ingredients NO magnesium stearate Gluten-free

Vegan formula

This product is free of: Milk, Salt, Yeast, Soy, Added Sugar, Wheat, Artificial Flavors and Preservatives.

We are committed to providing your family with additive-free formulas and superior nutrient forms in therapeutic amounts.

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested use: Adults, take two to three (2-3) capsules every 12 hours or as directed by a Health Care Practitioner.

Precautions

Keep Out of Reach of Children.

Do not use if safety seal on cap or printed inner seal is missing or broken.

Consult a physician if pregnant, lactating, currently on prescription medication or diagnosed with a medical condition.

Product is manufactured in a facility that processes milk, egg, soy, tree nuts, fish and shellfish.

Storage

Store in a Cool, Dry Place.

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

See for yourself

PureWay-C 500 mg by Emerald Labs label

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

PureWay-C 500 mg 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 PureWay-C 500 mg by Emerald Labs

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container45 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.

R-Alpha Lipoic Acid

Interacts with
263 drugs
25 mg per serving

Alpha-lipoic acid (ALA) is an antioxidant made naturally by the body and found in small amounts in foods. It is most studied for diabetic nerve pain,...

R-Alpha Lipoic Acid monograph & interactions

Vitamin C

Interacts with
207 drugs
500 mg per serving Form: Citrus Bioflavonoids, Pureway-C, Vegetable Fatty Acids

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

Other (inactive) ingredients: Vegetable Capsule. These complete the product’s ingredient list but are not active constituents.

Interaction report

PureWay-C 500 mg by Emerald Labs Drug Interactions

Want to check YOUR meds against PureWay-C 500 mg?

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

 Go to the checker
387Drugs
229 Moderate 158 Minor

Ingredients driving the most interactions

R-Alpha Lipoic Acid 263
Vitamin C 207

Individual Drug Interactions

The ingredients in PureWay-C 500 mg interact with 387 drugs. Click any drug to see the details.

2 of the 2 ingredients in PureWay-C 500 mg interact with drugs. Each result below shows which ingredient is responsible. R-Alpha Lipoic Acid Vitamin C

Each ingredient & the kinds of drugs it affects

For each ingredient in PureWay-C 500 mg 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.

R-Alpha Lipoic Acid5 drug types · 263 drugs

Alkylating Agents

Theoretically, the antioxidant effects of alpha-lipoic acid might alter the effectiveness of alkylating agents.
The use of antioxidants like alpha-lipoic acid during chemotherapy is controversial. There are concerns that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as alpha-lipoic acid have on chemotherapy. Advise patients to consult their oncologist before using alpha-lipoic acid.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, alpha-lipoic acid may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro, alpha-lipoic acid inhibits platelet aggregation.

Likelihood Possible Evidence D
Antitumor Antibiotics

Theoretically, the antioxidant effects of alpha-lipoic acid might alter the effectiveness of antitumor antibiotics.
The use of antioxidants like alpha-lipoic acid during chemotherapy is controversial. There are concerns that antioxidants could reduce the activity of antitumor antibiotic drugs, which work by generating free radicals. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as alpha-lipoic acid have on chemotherapy involving antitumor antibiotics. Advise patients to consult their oncologist before using alpha-lipoic acid.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, alpha-lipoic acid might decrease the effects of thyroid hormone drugs.
Animal research suggests that co-administration of thyroxine with alpha-lipoic acid reduces conversion into the active T3 form.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, taking alpha-lipoic acid with antidiabetes drugs might increase the risk of hypoglycemia.
Although some small clinical studies have suggested that alpha-lipoic acid can lower blood glucose levels, larger clinical studies in patients with diabetes have shown no clinically meaningful effect. Additionally, co-administration of single doses of alpha-lipoic acid and glyburide or acarbose did not cause detectable drug interactions in healthy volunteers.

Likelihood Unlikely Evidence B
R-Alpha Lipoic Acid 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
The maker

Brand information

Manufacturer and brand details for PureWay-C 500 mg, from the product label.

Emerald Labs

See all Emerald Labs products
Name
Emerald Laboratories
Street Address
20611 Belshaw Ave
City
Carson
State
CA
ZipCode
90746
Phone Number
(800) 436-4366
Web Address
www.emeraldlabs.com
Pharmacist Counseling Corner

PureWay-C 500 mg by Emerald Labs: Common Questions

Does PureWay-C 500 mg by Emerald Labs interact with any medications?
Yes. Based on its ingredients, PureWay-C 500 mg has a known interaction with 387 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
PureWay-C 500 mg contains 2 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 while on blood thinners?
Not without checking first — the alpha-lipoic acid in this product may increase bleeding risk when combined with blood thinners or antiplatelet drugs. Talk to your doctor or pharmacist before adding it.
Will this affect my thyroid medication?
Possibly. Alpha-lipoic acid may reduce thyroid hormone activity, and vitamin C can actually increase how much levothyroxine your body absorbs, which could affect your dose. Check with your doctor or pharmacist before using this product if you take thyroid medication.
Is this safe to take if I'm pregnant or breastfeeding?
The safety data advises against alpha-lipoic acid during pregnancy and breastfeeding. Vitamin C at normal dietary amounts is fine, but high-dose supplements should be avoided. Talk with your doctor or pharmacist for personalized guidance.
Can I take this with my birth control?
The vitamin C in this product may increase estrogen levels when taken with oral contraceptives, which could affect how well your birth control works. Talk with your doctor or pharmacist about whether this product is right for you.
What are the most common side effects?
From the alpha-lipoic acid: headache, heartburn, nausea, and vomiting. From the vitamin C: stomach cramps, heartburn, nausea, vomiting, and diarrhea — especially at higher doses. Most people tolerate both ingredients well, but these are the ones to watch for.
Does this actually work for high cholesterol or weight loss?
Alpha-lipoic acid is rated Possibly Effective for both high cholesterol and obesity, meaning there's some evidence but it's not definitive. Vitamin C is not rated for these uses. Results vary, and this shouldn't replace lifestyle changes or prescribed treatments.

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

Not sure if PureWay-C 500 mg is safe with your meds?

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

PureWay-C 500 mg label
Go deeper

The Full Monographs Behind PureWay-C 500 mg’s Ingredients

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

Herb & supplement monograph

Alpha-lipoic Acid

Interacts with 263 drugs

Alpha-lipoic acid (ALA) is an antioxidant made naturally by the body and found in small amounts in foods. It is most studied for diabetic nerve pain, where some evidence suggests it may help...

Read the full Alpha-lipoic Acid monograph → 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 →
Sources

Sources & How We Checked

PureWay-C 500 mg's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

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 99 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.

Alpha-lipoic Acid 48 references
  1. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  2. Anon. Alpha-lipoic acid. Altern Med Rev 1998;3:308-10.
  3. Konrad T, Vicini P, Kusterer K, et al. Alpha-lipoic acid treatment decreases serum lactate and pyruvate concentrations and improves glucose effectiveness in lean and obese patients with Type 2 diabetes. Diabetes Care 1999;22:280-7. PubMed
  4. Ziegler D, Hanefeld M, Ruhnau KJ, et al. Treatment of symptomatic diabetic peripheral neuropathy with the antioxidant alpha-lipoic acid: A 3-week, multicentre randomized controlled trial (ALADIN Study). Diabetologia 1995;38:1425-33.
  5. Gleiter CH, Schreeb KH, Freudenthaler S, et al. Lack of interaction between thioctic acid, glibenclamide and acarbose. Br J Clin Pharmacol 1999;48:819-25. PubMed
  6. Jacob S, Henriksen EJ, Tritschler HJ, et al. Improvement of insulin-stimulated glucose-disposal in type 2 diabetes after repeated parenteral administration of thioctic acid. Exp Clin Endocrinol Diabet 1996;104:284-8. PubMed
  7. Jacob S, Henriksen EJ, Schiemann AL, et al. Enhancement of glucose disposal in patients with type 2 diabetes by alpha-lipoic acid. Arzneimittelforschung 1995;45:872-4.
  8. Jacob S, Ruus P, Hermann R, et al. Oral administration of RAC-alpha-lipoic acid modulates insulin sensitivity in patients with type-2 diabetes mellitus: a placebo-controlled, pilot trial. Free Rad Biol Med 1999;27:309-14.
  9. Segermann J, Hotze A, Ulrich H, Rao GS. Effect of alpha-lipoic acid on the peripheral conversion of thyroxine to triiodothyronine and on serum lipid-, protein- and glucose levels. Arzneimittelforschung 1991;41:1294-8.
  10. Beitner H. Randomized, placebo controlled, double-blind study on the clinical efficacy of a cream containing 5% alpha-lipoic acid related to photoaging of facial skin. Br J Dermatol 2003;149:841-9.
  11. Ziegler D, Nowak H, Kempler P, et al. Treatment of symptomatic diabetic polyneuropathy with the antioxidant alpha-lipoic acid: A meta-analysis. Diabet Med 2004;21:114-21.
  12. 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
  13. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
  14. Vincent HK, Bourguignon CM, Vincent KR, Taylor AG. Effects of alpha-lipoic acid supplementation in peripheral arterial disease: a pilot study. J Alt Complement Med 2007;13:577-84. PubMed
  15. Furukawa N, Miyamura N, Nishida K, et al. Possible relevance of alpha lipoic acid contained in a health supplement in a case of insulin autoimmune syndrome. Diabetes Res Clin Pract 2007;75:366-7. PubMed
  16. Ziegler D., Ametov A., Barinov A., Dyck P. J., Gurieva I., Low P. A., Munzel U., Yakhno N., Raz I., Novosadova M., Maus J., Samigullin, R. Oral treatment with alpha-lipoic acid improves symptomatic diabetic polyneuropathy: the SYDNEY 2 trial. Diabetes Car
  17. Gu X. M., Zhang S. S., Wu J. C., Tang Z. Y., Lu Z. Q., Li H., Liu C., Chen L., Ning, G. [Efficacy and safety of high-dose a-lipoic acid in the treatment of diabetic polyneuropathy]. Zhonghua Yi Xue Za Zhi 2010;90(35):2473-2476.
  18. Porasuphatana S., Suddee S., Nartnampong A., Konsil J., Harnwong B., Santaweesuk A. Glycemic and oxidative status of patients with type 2 diabetes mellitus following oral administration of alpha-lipoic acid: a randomized double-blinded placebo-controlled
  19. Ansar H., Mazloom Z., Kazemi F., Hejazi N. Effect of alpha-lipoic acid on blood glucose, insulin resistance and glutathione peroxidase of type 2 diabetic patients. Saudi Med J 2011;32(6):584-588. DOI
  20. de Oliveira A. M., Rondó P. H., Luzia L. A., D'Abronzo F. H., Illison V. K. The effects of lipoic acid and a-tocopherol supplementation on the lipid profile and insulin sensitivity of patients with type 2 diabetes mellitus: a randomized, double-blind, pla
  21. Mazloom Z., Ansar H. The Effect of Alpha-Lipoic Acid on Blood Pressure in Type 2 Diabetics. Iranian Journal of Endocrinology and Metabolism 2009;11(3):245-250.
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  38. Sun Y, Guan X, Wang H, et al. Randomized clinical trial of combined therapy with oral a-lipoic acid and NB-UVB for nonsegmental stable vitiligo. Dermatol Ther. 2021;34(1):e14610.
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  44. EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA), Turck D, et al. Scientific opinion on the relationship between intake of alpha-lipoic acid (thioctic acid) and the risk of insulin autoimmune syndrome. EFSA J 2021;19(6):e06577. PubMed
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  47. Velasco-Amador JP, Prados-Carmona Á, Navarro-Triviño FJ. Contact urticaria syndrome caused by alpha-lipoic acid in a master formula for vulvar lichen sclerosus. Contact Dermatitis 2023;89(2):136-137. PubMed
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See these in context on the Alpha-lipoic Acid monograph →

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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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