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Dietary supplement

L-Carnitine 2000 Ingredients & Drug Interactions

by Body Attack

L-Carnitine 2000 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 L-Carnitine 2000 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

L-Carnitine 2000 is a dietary supplement by Body Attack with 3 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 220 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin C, L-Carnitine Tartrate. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against L-Carnitine 2000 by Body Attack

Ask about any prescription or over-the-counter medication and we check it for interactions with L-Carnitine 2000 by Body Attack — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of L-Carnitine 2000 by Body Attack

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 11, 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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

L-Carnitine 2000 contains 3 active ingredients. Vitamin C supports immune function and acts as an antioxidant.

Biotin is a B vitamin that plays a role in energy metabolism and may support hair, skin, and nail health. L-Carnitine Tartrate is an amino acid derivative that helps transport fatty acids so your cells can burn them for energy.

The product also contains several inactive ingredients — fillers and binders — to hold the capsule together.

Does it work?

Insufficient 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
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Boost focus, energy support and exercise performance.
  • We looked for evidence on: Athletic performance, Exercise-induced muscle damage, Exercise-induced muscle soreness, Endurance, Stamina, Workout recovery.
  • The closest evidence on file: Vitamin C is rated "Insufficient Reliable Evidence To Rate" for Athletic performance (Natural Medicines).
  • Also on file: Vitamin C is rated "Insufficient Reliable Evidence To Rate" for Exercise-induced muscle damage.
  • Also on file: L-carnitine is rated "Insufficient Reliable Evidence To Rate" for Athletic performance, Exercise-induced muscle soreness, Exercise-induced muscle damage.

Vitamin C is effective for preventing and treating vitamin C deficiency, and there's possibly good evidence it may help with anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections. Biotin is likely effective for biotin deficiency; evidence for other uses like multiple sclerosis, seborrheic dermatitis, and hair loss is either possibly ineffective or we don't have reliable data to rate it.

L-Carnitine appears effective for L-carnitine deficiency and possibly effective for high cholesterol, congestive heart failure, and angina. The evidence we hold doesn't establish this product's effectiveness for any other specific condition beyond what the individual ingredients show.

The evidence, ingredient by ingredient Vitamin C Biotin L-carnitine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

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

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

Vitamin C is generally well tolerated at normal doses, but very high doses can cause abdominal cramps, heartburn, diarrhea, nausea, and vomiting — and in people prone to them, kidney stones. Biotin is generally considered safe and well tolerated, even at fairly high doses, because your body excretes excess through urine; mild diarrhea has been rarely reported at very high doses.

L-Carnitine is generally well tolerated, but can cause abdominal cramps, diarrhea, heartburn, nausea, and a fishy body odor at higher doses. Vitamin C safety data in pregnancy and breastfeeding is mixed — normal amounts from food and prenatal vitamins are fine, but high-dose supplements should be avoided unless your doctor recommends them.

Biotin is likely safe in pregnancy and breastfeeding. L-Carnitine has no pregnancy or breastfeeding safety data on file — talk with your doctor before use if you're pregnant or breastfeeding.

Side effects, ingredient by ingredient Vitamin C Biotin L-carnitine

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 3 matched ingredients can interact with medications — Vitamin C, L-carnitine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments.
  • For scale: 220 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your pharmacist if you're on blood thinners like warfarin or acenocoumarol — L-Carnitine may enhance their effect, and high-dose vitamin C can reduce warfarin's effectiveness. Vitamin C also interacts with hormonal birth control or hormone replacement therapy (estrogen levels may rise), certain chemotherapy drugs, thyroid medication like levothyroxine, and the antipsychotic fluphenazine.

Aluminum-based antacids and L-carnitine's effect on thyroid hormone are other Moderate-severity concerns to discuss.

Check your own medication Run your meds through the checker above

The bottom line

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

This product may help if you have a deficiency in any of its three nutrients or want general antioxidant and energy support, but it interacts with blood thinners, hormonal birth control, thyroid medication, and chemotherapy drugs — check with your pharmacist before starting if you take any of these. The vitamin C content is the main concern for drug interactions.

If you're pregnant, breastfeeding, or have kidney problems, talk with your doctor first.

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

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated May 21, 2025.

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 L-Carnitine 2000, straight from the product label.

Brand Body Attack
Barcode (UPC) 4250350547588
Net contents 100 Vegan Cap(s); 89 Gram(s)
Market status On market
Date entered into DSLD May 21, 2025
DSLD ID 329583
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
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 L-Carnitine 2000 by Body Attack, 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:
4 Capsule(s)
Maximum serving Sizes:
4 Capsule(s)
Servings per container
30
UPC/BARCODE
4250350547588
IngredientAmount% DV
Vitamin C110 mg138%
Biotin50 mcg100%
L-Carnitine Tartrate2932 mg--

Other ingredients: Hydroxypropyl Methylcellulose, L-Ascorbic Acid, Magnesium Stearate, D-Biotin

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.
Formulation

High bioavailability

Suggested/Recommended/Usage/Directions

Recommended dosage: On training days, take 4 capsules 45 minutes before training. On non-training days, take 2 capsules in the morning and in the evening before bed time with plenty of liquid (200 mL).

Precautions

Do not exceed the recommended daily dosage.

Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle.

Keep out of reach of small children.

Seals/Symbols

Made in Germany

Formula

Boost formula for focus & energy support Biotin contributes to normal psychological function. Vitamin C contributes to a normal energy-yielding metabolism

Per daily serving: 2000 mg L-carnitine 110 mg vitamin C 50 mcg biotin Food supplement in capsule form with L-carnitine, vitamin C and biotin.

FDA Statement of Identity

Food Supplement in capsule form with L-carnitine, vitamin C and biotin.

Storage

If kept unopened in a cool, dry place, best before end of/Lot No.: see bottom. Once opened, use up quickly. Keep away from direct heat and light.

General Statements

%NRV NRV = % of Nutrient Reverence Values 89 g = 100 capsules (890 mg each) = 25 servings

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

See for yourself

L-Carnitine 2000 by Body Attack label

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

L-Carnitine 2000 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 L-Carnitine 2000 by Body Attack

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

Serving size4 Capsule(s) Dosage formCapsule 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
110 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...

Vitamin C monograph & interactions

Biotin

No known
interactions
50 mcg per serving

Biotin (vitamin B7) is a water-soluble vitamin your body needs to turn food into energy and to support healthy hair, skin, and nails. Most people get...

Biotin monograph & interactions

L-Carnitine Tartrate

Interacts with
19 drugs
2932 mg per serving

L-carnitine is a compound your body makes naturally and also gets from foods like meat. It helps cells turn fat into energy, and supplements are most...

L-Carnitine Tartrate monograph & interactions

Other (inactive) ingredients: Hydroxypropyl Methylcellulose, L-Ascorbic Acid, Magnesium Stearate, D-Biotin. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Carnitine 2000 by Body Attack Drug Interactions

Want to check YOUR meds against L-Carnitine 2000?

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
220Drugs
114 Moderate 106 Minor

Ingredients driving the most interactions

Vitamin C 207
L-Carnitine Tartrate 19

Individual Drug Interactions

The ingredients in L-Carnitine 2000 interact with 220 drugs. Click any drug to see the details.

2 of the 3 ingredients in L-Carnitine 2000 interact with drugs. Each result below shows which ingredient is responsible. Vitamin C L-Carnitine Tartrate

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Carnitine 2000 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.

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

L-Carnitine Tartrate3 drug types · 19 drugs

Acenocoumarol (Sintrom)

Theoretically, L-carnitine might increase the anticoagulant effects of acenocoumarol.
L-carnitine might enhance the anticoagulant effects of acenocoumarol, an oral anticoagulant similar to warfarin, but shorter-acting. There are at least two case reports of INR elevation with concomitant use. In one case, a 33-year-old male with a previously stable INR had an elevated INR of 4.65 after L-carnitine was started and continued for 10 weeks. INR normalized after discontinuation of the L-carnitine-containing product.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, L-carnitine might decrease the effectiveness of thyroid hormone replacement.
L-carnitine appears to act as a peripheral thyroid hormone antagonist by inhibiting entry of thyroid hormone into the nucleus of cells. Taking L-carnitine also seems to diminish some of the symptoms of hyperthyroidism.

Likelihood Probable Evidence B
Warfarin (Coumadin)

Theoretically, L-carnitine might increase the anticoagulant effects of warfarin.
L-carnitine might increase the anticoagulant effects of acenocoumarol, a shorter-acting oral anticoagulant similar to warfarin. There is not enough information to know whether this interaction occurs with L-carnitine and warfarin.

Likelihood Possible Evidence D
L-Carnitine Tartrate full monograph & interactions
The maker

Brand information

Manufacturer and brand details for L-Carnitine 2000, from the product label.

Body Attack

See all Body Attack products
Name
Body Attack Sports Nutrition GmbH & Co. KG
Street Address
Schnackenburgalle 217-223
City
Hamburg
ZipCode
22525
Web Address
www.body-attack.com
Pharmacist Counseling Corner

L-Carnitine 2000 by Body Attack: Common Questions

Does L-Carnitine 2000 by Body Attack interact with any medications?
Yes. Based on its ingredients, L-Carnitine 2000 has a known interaction with 220 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Carnitine 2000 contains 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Does this product have side effects?
At normal doses, all three ingredients are generally well tolerated. Vitamin C can cause stomach upset, heartburn, and diarrhea at high doses. L-Carnitine may cause abdominal cramps, diarrhea, nausea, and rarely a fishy body odor. Biotin is generally very safe, though very high doses have rarely caused mild diarrhea. If you notice any of these, lower your dose or stop and talk to your pharmacist.
Can I take this if I'm pregnant or breastfeeding?
The normal amounts of vitamin C and biotin in prenatal vitamins are fine, but this product contains higher doses — check with your doctor before use. L-Carnitine has no reliable safety data in pregnancy or breastfeeding, so discuss it with your doctor or pharmacist for personalized advice before starting.
Will this help me lose weight or get more energy?
L-Carnitine helps your cells use fat for fuel, and there's some evidence it may help with muscle endurance and recovery, but this product's effectiveness for weight loss or general energy isn't established in the data we hold. Your best bet is to talk with your pharmacist about what the research actually shows for your specific goal.
What is L-Carnitine Tartrate, and why is it in this product?
L-Carnitine Tartrate is an amino acid that helps transport fat into your cells so they can burn it for energy. It's effective for treating L-carnitine deficiency and may help with heart failure, high cholesterol, and angina — that's why it's included here.
Is this safe if I have kidney problems?
Vitamin C at very high doses can be a concern for people with kidney disease — high-dose vitamin C can lead to kidney stones or worsen kidney function. Talk with your doctor before taking this product if you have kidney disease or a history of kidney stones.
Can this interact with my multivitamin?
That depends on what's in your multivitamin and the doses. If your multivitamin also contains vitamin C, biotin, or L-carnitine, you could be getting more than you intend — check the labels and talk to your pharmacist to make sure the total dose is safe.

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.

L-Carnitine 2000 label
Go deeper

The Full Monographs Behind L-Carnitine 2000’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

Biotin

Biotin (vitamin B7) is a water-soluble vitamin your body needs to turn food into energy and to support healthy hair, skin, and nails. Most people get plenty from a normal diet, and true defi...

Read the full Biotin monograph → Herb & supplement monograph

L-carnitine

Interacts with 19 drugs

L-carnitine is a compound your body makes naturally and also gets from foods like meat. It helps cells turn fat into energy, and supplements are most clearly useful for people with a true ca...

Read the full L-carnitine monograph →
Sources

Sources & How We Checked

L-Carnitine 2000'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 96 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
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