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

Lipoic 300 mg Ingredients & Drug Interactions

by Bio-Tech Pharmacal

Lipoic 300 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 Lipoic 300 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

Lipoic 300 mg is a dietary supplement by Bio-Tech Pharmacal with 2 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 387 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Alpha Lipoic Acid, Ascorbic Acid. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Lipoic 300 mg by Bio-Tech Pharmacal

Ask about any prescription or over-the-counter medication and we check it for interactions with Lipoic 300 mg by Bio-Tech Pharmacal — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Lipoic 300 mg by Bio-Tech Pharmacal

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 Aug 13, 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.

This product contains 2 active ingredients: ascorbic acid (vitamin C) and alpha-lipoic acid. Vitamin C is an essential nutrient needed for immune function, collagen formation, and antioxidant protection.

Alpha-lipoic acid is a compound your body makes naturally; it plays a role in energy production and acts as an antioxidant. The capsule shell itself is made from hydroxypropyl methylcellulose, a plant-based material.

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: Diabetic neuropathy — rated "Possibly Effective" (Alpha-lipoic Acid) (Natural Medicines).

For vitamin C: the evidence supports it as effective for vitamin C deficiency. It's possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections.

For alpha-lipoic acid: evidence suggests it's possibly effective for diabetic nerve pain (neuropathy), high cholesterol (hyperlipidemia), and obesity. The strength of evidence for these uses isn't as robust as it is for treating a frank vitamin C shortage.

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

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.

Vitamin C is generally well tolerated at normal supplement doses, but very high doses — above 2 grams daily — are more likely to cause side effects like stomach cramps, heartburn, diarrhea, nausea, and headache. People prone to kidney stones should be cautious, as high-dose vitamin C can contribute to stone formation.

Alpha-lipoic acid is generally well tolerated and most commonly causes mild headache, heartburn, nausea, or vomiting. For pregnancy: vitamin C from normal food and prenatal vitamins is fine, but avoid high-dose supplements unless your doctor advises it.

Alpha-lipoic acid should be avoided during pregnancy and breastfeeding because there isn't enough reliable safety data.

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

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.

Check before taking if you use blood thinners or antiplatelet drugs (like warfarin or aspirin), hormonal birth control or hormone replacement therapy, thyroid medications, diabetes drugs, chemotherapy, or an antipsychotic like fluphenazine. Also mention any aluminum-containing antacids or supplements.

The vitamin C in this product can affect how these work.

Check your own medication Run your meds through the checker above

The bottom line

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

This product may help with vitamin C deficiency and possibly with nerve pain or cholesterol issues, but its two ingredients interact with quite a few medications — especially blood thinners, birth control, thyroid drugs, and chemotherapy. If you take any prescription medications or have upcoming surgery, talk with your doctor or pharmacist before starting this supplement.

They can review your specific drugs and determine whether it's appropriate for you.

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 Apr 23, 2020.

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 Lipoic 300 mg, straight from the product label.

Brand Bio-Tech Pharmacal
Barcode (UPC) 705105105505
Net contents 100 Vegetable Capsule(s)
Market status On market
Date entered into DSLD Apr 23, 2020
DSLD ID 217409
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Kosher, Halal, Gluten Free, Dairy Free, Sugar Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Lipoic 300 mg by Bio-Tech Pharmacal, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
UPC/BARCODE
705105105505
IngredientAmount% DV
Ascorbic Acid100 mg111%
Alpha Lipoic Acid300 mg--

Other ingredients: Hydroxypropyl Methylcellulose (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.
Precautions

Keep out of the reach of children.

Safety sealed for your protection.

Storage

Store tightly closed in a cool, dry place.

Suggested/Recommended/Usage/Directions

Suggested Use: One capsule per day or as directed by a healthcare professional.

Formulation

Contains No: Dairy, egg, fish, shellfish, nuts, wheat, gluten, soy, sugar, yeast, artificial preservatives or colors.

Gluten free Non GMO

New improved formula

cGMP Current Good Manufacturing Practice

Formula

Kosher and Halal certified.

Kosher and Halal certified.

General Statements

Energy = Health

PNR Over 100 Partners in Research

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

cGMP Current Good Manufacturing Practice

EarthKosher

ISWA Halal

Made in the USA

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

See for yourself

Lipoic 300 mg by Bio-Tech Pharmacal label

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

Lipoic 300 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 Lipoic 300 mg by Bio-Tech Pharmacal

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

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

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

Ascorbic Acid

Interacts with
207 drugs
100 mg per serving

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...

Ascorbic Acid monograph & interactions

Alpha Lipoic Acid

Interacts with
263 drugs
300 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,...

Alpha Lipoic Acid monograph & interactions

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

Interaction report

Lipoic 300 mg by Bio-Tech Pharmacal Drug Interactions

Want to check YOUR meds against Lipoic 300 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

Alpha Lipoic Acid 263
Ascorbic Acid 207

Individual Drug Interactions

The ingredients in Lipoic 300 mg interact with 387 drugs. Click any drug to see the details.

2 of the 2 ingredients in Lipoic 300 mg interact with drugs. Each result below shows which ingredient is responsible. Alpha Lipoic Acid Ascorbic Acid

Each ingredient & the kinds of drugs it affects

For each ingredient in Lipoic 300 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.

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
Alpha Lipoic Acid full monograph & interactions

Ascorbic Acid13 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
Ascorbic Acid full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Lipoic 300 mg, from the product label.

Bio-Tech Pharmacal

See all Bio-Tech Pharmacal products
Name
Bio-Tech
City
Fayetteville
State
AR
ZipCode
72704
Phone Number
1-800-345-1199
Web Address
www.BioTechPharmacal.com
Pharmacist Counseling Corner

Lipoic 300 mg by Bio-Tech Pharmacal: Common Questions

Does Lipoic 300 mg by Bio-Tech Pharmacal interact with any medications?
Yes. Based on its ingredients, Lipoic 300 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?
Lipoic 300 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 if I'm on birth control?
Not without checking first. The vitamin C in this product can increase how much estrogen your body absorbs from hormonal contraceptives, which could affect how well the birth control works or raise your risk of side effects. Talk to your doctor or pharmacist before taking it — they may need to adjust your dose or monitor you more closely.
Is this safe if I have a history of kidney stones?
Vitamin C at very high doses can increase kidney stone risk in people prone to them. This product contains ascorbic acid, so you should discuss it with your doctor before starting, especially if stones run in your family or you've had them before.
What's the difference between vitamin C and alpha-lipoic acid in this product?
Vitamin C is an essential nutrient your body can't make; you need it from food or supplements. Alpha-lipoic acid is a compound your body produces naturally and uses for energy; it's added here as a supplement for its antioxidant effects. Both are active ingredients, and both interact with certain medications.
Will this help my cholesterol or blood sugar?
Alpha-lipoic acid is possibly effective for high cholesterol and possibly effective for weight management, and it may help with diabetic nerve pain. The evidence isn't as strong as for treating a vitamin C deficiency, but some people see modest benefits. Your doctor can help you decide if it's worth trying.
Is this safe to take during pregnancy?
Vitamin C from normal food and prenatal vitamins is fine. But high-dose vitamin C supplements are best avoided unless your doctor says otherwise. Alpha-lipoic acid should be avoided during pregnancy because there isn't enough safety data. Talk with your doctor if you're thinking about taking this product.
What are the most common side effects?
From vitamin C: stomach cramps, heartburn, diarrhea, nausea, and headache — more likely at doses above 2 grams daily. From alpha-lipoic acid: headache, heartburn, nausea, and vomiting. These are usually mild, but let your doctor know if they don't settle down.

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.

Lipoic 300 mg label
Go deeper

The Full Monographs Behind Lipoic 300 mg’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

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 →
Sources

Sources & How We Checked

Lipoic 300 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.

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  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/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  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
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  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
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
  20. Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
  21. Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
  22. Vihtamaki T, Parantainen J, Koivisto AM, et al. Oral ascorbic acid increases plasma oestradiol during postmenopausal hormone replacement therapy. Maturitas 2002;42:129-35. PubMed
  23. Slain D, Amsden JR, Khakoo RA, et al. Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers. Pharmacotherapy 2005;25:165-70. PubMed
  24. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
  25. Feetam CL, Leach RH, Meynell MJ. Lack of a clinically important interaction between warfarin and ascorbic acid. Toxicol Appl Pharmacol 1975;31:544-7. PubMed
  26. Weintraub M, Griner PF. Warfarin and ascorbic acid: lack of evidence for a drug interaction. Toxicol Appl Pharmacol 1974;28:53-6. PubMed
  27. Lee DH, Folsom AR, Harnack L, et al. Does supplemental vitamin C increase cardiovascular disease risk in women with diabetes? Am J Clin Nutr 2004;80:1194-200. PubMed
  28. Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-32. PubMed
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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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