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Dietary supplement

Carnitine 2000 mg Ingredients & Drug Interactions

by ILN Iron Labs Nutrition

Capsule Category: Other Combinations
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Carnitine 2000 mg is a dietary supplement by ILN Iron Labs Nutrition with 6 active ingredients. Its ingredients are commonly taken for riboflavin deficiency, migraine prevention, general energy and metabolism support.Based on those ingredients, 1,279 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Niacin, Vitamin D, Acetyl-L-Carnitine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Carnitine 2000 mg by ILN Iron Labs Nutrition

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

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 6 of its 6 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Carnitine 2000 mg contains six active ingredients. The main ingredient is acetyl-L-carnitine, which plays a role in energy production in cells.

It's joined by riboflavin (vitamin B2), biotin (vitamin B7), chromium, niacin (vitamin B3), and vitamin D—all supporting various metabolic and nutritional functions. The capsule also contains inactive ingredients like rice flour, magnesium stearate, and silicon dioxide, which are standard binders and flow agents.

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: Familial hypophosphatemia — rated "Effective" (Vitamin D) (Natural Medicines).
  • On file: Osteomalacia — rated "Effective" (Vitamin D) (Natural Medicines).
  • On file: Renal osteodystrophy — rated "Effective" (Vitamin D) (Natural Medicines).
  • On file: Rickets — rated "Effective" (Vitamin D) (Natural Medicines).
  • On file: Hypoparathyroidism — rated "Effective" (Vitamin D) (Natural Medicines).

The effectiveness data we hold covers several of the individual ingredients. Acetyl-L-carnitine is rated Possibly Effective for age-related cognitive decline, Alzheimer disease, diabetic neuropathy, depression, and alcohol use disorder.

Niacin is Possibly Effective for metabolic syndrome and HIV/AIDS-related dyslipidemia, and Likely Effective for pellagra. Chromium is Possibly Effective for diabetes and Likely Effective for chromium deficiency.

Vitamin D is Effective for rickets, renal osteodystrophy, osteomalacia, familial hypophosphatemia, and hypoparathyroidism. Biotin is Likely Effective for biotin deficiency but Possibly Ineffective for multiple sclerosis and seborrheic dermatitis.

We have no effectiveness data on file for riboflavin in this product.

The evidence, ingredient by ingredient Riboflavin Biotin Chromium Niacin Vitamin D Acetyl-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 6 of the 6 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 6 of 6.
  • General safety write-ups exist for 6 of 6.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of these ingredients are generally well tolerated at typical doses. Riboflavin is considered very safe and is needed during pregnancy and breastfeeding at recommended amounts, though high-dose supplements warrant a talk with your provider.

It may cause dose-related nausea and bright yellow urine. Biotin is generally safe and well tolerated, even at fairly high doses; normal dietary and supplement amounts are appropriate during pregnancy and breastfeeding, but discuss high-dose products with your doctor first.

Chromium is usually well tolerated at typical supplement doses, but high or long-term doses may pose risks; avoid extra chromium in pregnancy and breastfeeding unless your doctor recommends it. Common side effects include gastrointestinal irritation, headaches, and insomnia; rare cases of kidney damage, liver damage, and blood disorders have been reported.

Niacin at high supplemental doses can cause flushing, liver problems, and gastrointestinal upset; normal dietary amounts are safe. Amounts from food and standard prenatal vitamins are fine, but high-dose niacin should be avoided unless prescribed.

Vitamin D is generally safe at recommended doses but can cause toxicity at very high doses over time; amounts from food and prenatal vitamins are acceptable during pregnancy, but use only under your doctor's guidance. Acetyl-L-carnitine is generally well tolerated short-term, though long-term safety is not fully established; common side effects include agitation, dry mouth, headache, insomnia, and reduced appetite.

Safety information during breastfeeding is unknown, so avoiding it is the safer choice. Pregnancy safety data for acetyl-L-carnitine are not on file.

Side effects, ingredient by ingredient Riboflavin Biotin Chromium Niacin Vitamin D Acetyl-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?
  • 5 of the 6 matched ingredients can interact with medications — Acetyl-l-carnitine, Niacin, Vitamin D, Chromium, Riboflavin.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; heart-rhythm medications.
  • For scale: 1,280 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 take any antidiabetes drugs or insulin (chromium and niacin may lower blood sugar further), tetracycline antibiotics (riboflavin may reduce potency), thyroid hormone like levothyroxine (chromium may reduce absorption), blood thinners like warfarin (acetyl-L-carnitine may increase effects), thiazide diuretics (vitamin D may raise blood calcium), heart medications like verapamil or digoxin (vitamin D may interfere), atorvastatin (vitamin D may reduce levels), serotonergic drugs such as antidepressants (acetyl-L-carnitine may increase serotonin effects), or NSAIDs and aspirin (may increase chromium levels).

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 combines several B vitamins, chromium, vitamin D, and acetyl-L-carnitine—ingredients with different roles in metabolism and cognition. If you take blood-sugar medications, thyroid hormone, blood thinners, or serotonergic drugs like antidepressants, you'll want to check your exact medications with the tool on this page before starting.

Talk with your pharmacist about whether this product fits your health needs and current medications.

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

Assessment coverage: 6 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 21, 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 Carnitine 2000 mg, straight from the product label.

Brand ILN Iron Labs Nutrition
Barcode (UPC) X000UTXGZF
Net contents 120 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Feb 21, 2023
DSLD ID 286923
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 Carnitine 2000 mg by ILN Iron Labs Nutrition, 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
X000UTXGZF
IngredientAmount% DV
Riboflavin4 mg286%
Biotin200 mcg400%
Chromium80 mcg200%
Niacin4 mg NE25%
Vitamin D2 mcg40%
Acetyl-L-Carnitine2000 mg--

Other ingredients: Hydroxypropyl Methylcellulose, Rice Flour, Magnesium Stearate, Silicon Dioxide, Pyridoxine Hydrochloride, Nicotinamide, Cholecalciferol, Chromium Picolinate, 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.
Suggested/Recommended/Usage/Directions

Directions: Take 4 capsules once per day. Take capsules with a glass of water.

Precautions

Important Information: Do not exceed recommended daily dosage. Food supplements must not be used as a substitute for a varied and balanced diet and a healthy lifestyle.

Not recommended for use by pregnant or lactating women. If you are taking any medications, are under medical supervision, have an existing medical condition or symptoms of illness, consult your doctor before use.

Using this supplement at the same time as other food supplements may result in excessive nutrient dosages, consult a qualified professional if you are unsure. Discontinue use and contact a doctor immediately if any adverse reactions occur.

Not intended for use by persons under the of 18.

Do not use if seal is broken or missing.

Keep out of the reach of children.

FDA Disclaimer Statement

This product is a food supplement and is not intended to diagnose, treat, cure or prevent any medical condition, illness or disease.

Storage

Store in a cool, dry place.

Formula

Acetyl-L-Carnitine Acetyl L Carnitine with 6 added nutrients providing 2000 mg per serving

FDA Statement of Identity

Food Supplement

Formulation

Suitable for vegetarians.

Brand IP Statement(s)

ILN and Iron Labs Nutrition are registered trademarks of Euro Nutrition Ltd in the UK

See for yourself

Carnitine 2000 mg by ILN Iron Labs Nutrition label

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

What’s inside

The Ingredients in Carnitine 2000 mg by ILN Iron Labs Nutrition

These are the 6 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.

Riboflavin

Interacts with
20 drugs
4 mg per serving Form: Vitamin B2

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally...

Riboflavin monograph & interactions

Biotin

No known
interactions
200 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

Chromium

Interacts with
178 drugs
80 mcg per serving

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control i...

Chromium monograph & interactions

Niacin

Interacts with
727 drugs
4 mg NE per serving Form: Vitamin B3

Niacin (vitamin B3) is an essential nutrient your body needs for energy and metabolism, and deficiency is uncommon in most developed countries. Prescr...

Niacin monograph & interactions

Vitamin D

Interacts with
715 drugs
2 mcg per serving Form: Vitamin D3

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people,...

Vitamin D monograph & interactions

Acetyl-L-Carnitine

Interacts with
203 drugs
2000 mg per serving

Acetyl-L-carnitine is a form of the amino acid carnitine that the body uses to help produce energy in cells. It is most studied for nerve pain and mem...

Acetyl-L-Carnitine monograph & interactions

Other (inactive) ingredients: Hydroxypropyl Methylcellulose, Rice Flour, Magnesium Stearate, Silicon Dioxide, Pyridoxine Hydrochloride, Nicotinamide, Cholecalciferol, Chromium Picolinate, D-Biotin. These complete the product’s ingredient list but are not active constituents.

Interaction report

Carnitine 2000 mg by ILN Iron Labs Nutrition Drug Interactions

Want to check YOUR meds against Carnitine 2000 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
1,279Drugs
899 Moderate 380 Minor

Ingredients driving the most interactions

Niacin 727
Vitamin D 715
Chromium 178

Each ingredient & the kinds of drugs it affects

For each ingredient in Carnitine 2000 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.

Niacin15 drug types · 727 drugs

Alcohol (Ethanol)

Concomitant use of alcohol and niacin might increase the risk of flushing and hepatotoxicity.
Alcohol can exacerbate the flushing and pruritus associated with niacin. Large doses of niacin might also exacerbate liver dysfunction associated with chronic alcohol use. A case report describes delirium and lactic acidosis in a patient taking niacin 3 grams daily who ingested 1 liter of wine. Advise patients to avoid large amounts of alcohol while taking niacin.

Likelihood Probable Evidence D
Allopurinol (Zyloprim)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as allopurinol.
Large doses of niacin can reduce urinary excretion of uric acid, potentially resulting in hyperuricemia. Doses of uricosurics such as allopurinol might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Anticoagulant/Antiplatelet Drugs

Theoretically, niacin may have additive effects when used with anticoagulant or antiplatelet drugs.
Several cases of clotting factor synthesis deficiency and coagulopathy have been reported in patients taking sustained-release niacin. Also, thrombocytopenia has been reported in patients treated with niacin or niacin plus lovastatin.

Likelihood Possible Evidence D
Antidiabetes Drugs

Niacin can increase blood glucose levels and may diminish the effects of antidiabetes drugs.
Niacin impairs glucose tolerance in a dose-dependent manner, probably by causing or aggravating insulin resistance and increasing hepatic production of glucose. In diabetes patients, niacin 4.5 grams daily for 5 weeks can increase plasma glucose by an average of 16% and glycated hemoglobin (HbA1c) by 21%. However, lower doses of 1.5 grams daily or less appear to have minimal effects on blood glucose. In some patients, glucose levels increase when niacin is started, but then return to baseline when a stable dose is reached. Up to 35% of patients with diabetes may need adjustments in hypoglycemic therapy when niacin is added.

Likelihood Probable Evidence B
Antihypertensive Drugs

Theoretically, niacin may increase the risk of hypotension when used with antihypertensive drugs.
The vasodilating effects of niacin can cause hypotension. Furthermore, some clinical evidence suggests that a one-hour infusion of niacin can reduce systolic, diastolic, and mean blood pressure in hypertensive patients. This effect is not observed in normotensive patients.

Likelihood Possible Evidence B
Bile Acid Sequestrants

Bile acid sequestrants can bind niacin and decrease absorption. Separate administration by 4-6 hours to avoid an interaction.
In vitro studies show that colestipol (Colestid) binds about 98% of available niacin and cholestyramine (Questran) binds 10% to 30%.

Likelihood Possible Evidence D
Gemfibrozil (Lopid)

Theoretically, concomitant use of niacin and gemfibrozil might increase the risk of myopathy in some patients.
A case of myopathy from concomitant use of niacin and gemfibrozil has been reported. Niacin alone has also been associated with cases of myopathy. Using gemfibrozil with niacin might further increase the risk of developing myopathy.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use of niacin and hepatotoxic drugs might increase the risk of hepatotoxicity.
Niacin has been associated with cases of liver toxicity, especially when used in pharmacologic doses. Sustained-release niacin preparations appear to be associated with a higher risk of hepatotoxicity than immediate-release niacin.

Likelihood Possible Evidence D
Hmg-Coa Reductase Inhibitors ("Statins")

Theoretically, concomitant use of niacin and statins might increase the risk of myopathy and rhabdomyolysis in some patients.
Some case reports have raised concerns that niacin might increase the risk of myopathy and rhabdomyolysis when combined with statins. However, a significantly increased risk of myopathy has not been demonstrated in clinical trials, including those using an FDA-approved combination of lovastatin and niacin (Advicor).

Likelihood Possible Evidence D
Probenecid (Benemid)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as probenecid.
Large doses of niacin reduce urinary excretion of uric acid, potentially causing hyperuricemia. Doses of uricosurics such as probenecid might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Sulfinpyrazone (Anturane)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as sulfinpyrazone.
Large doses of niacin reduce urinary excretion of uric acid, potentially causing hyperuricemia. Doses of uricosurics such as sulfinpyrazone might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Thyroid Hormone

Theoretically, niacin might antagonize the therapeutic effects of thyroid hormones.
Clinical research and case reports suggests that taking niacin can reduce serum levels of thyroxine-binding globulin by up to 25% and moderately reduce levels of thyroxine (T4). Patients taking thyroid hormone for hypothyroidism might need dose adjustments when using niacin.

Likelihood Probable Evidence D
Transdermal Nicotine (Nicoderm)

Theoretically, concomitant use of niacin and transdermal nicotine might increase the risk of flushing and dizziness.
Niacin and nicotine can both cause flushing and dizziness.

Likelihood Possible Evidence D
Warfarin (Coumadin)

There is limited evidence that niacin may increase the anticoagulant effects of warfarin.
In a case report, a patient on warfarin developed an elevated international normalized ratio (INR) of 3.9 after taking niacin for two weeks. The patient's INR was previously stable, ranging between 2 and 3 in recent months, and no other medication changes were identified. The elevated INR returned to therapeutic range within 4 days following the discontinuation of niacin.

Likelihood Possible Evidence D
Aspirin

Large doses of aspirin might alter the clearance of niacin.
Aspirin is often used with niacin to reduce niacin-induced flushing. Doses of 80-975 mg aspirin have been used, but 325 mg appears to be optimal. Aspirin also seems to reduce the clearance of niacin by competing for glycine conjugation. Taking aspirin 1 gram seems to reduce niacin clearance by 45%. This is probably a dose-related effect and not clinically significant with the more common aspirin dose of 325 mg.

Likelihood Likely Evidence B

Vitamin D8 drug types · 715 drugs

Aluminum

Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
The protein that transports calcium across the intestinal wall can also bind and transport aluminum. This protein is stimulated by vitamin D, which may therefore increase aluminum absorption. This mechanism may contribute to increased aluminum levels and toxicity in people with renal failure, when they take vitamin D and aluminum-containing phosphate binders chronically.

Likelihood Probable Evidence B
Atorvastatin (Lipitor)

Vitamin D might reduce absorption of atorvastatin.
A small, low-quality clinical study shows that taking vitamin D reduces levels of atorvastatin and its active metabolites by up to 55%. However, while atorvastatin levels decreased, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol levels did not substantially change. Atorvastatin is metabolized in the gut by CYP3A4 enzymes, and researchers theorized that vitamin D might induce CYP3A4, causing reduced levels of atorvastatin. However, this proposed mechanism was not specifically studied.

Likelihood Probable Evidence B
Calcipotriene (Dovonex)

Taking calcipotriene with vitamin D increases the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with vitamin D supplements might increase the risk of hypercalcemia.

Likelihood Probable Evidence D
Digoxin (Lanoxin)

Theoretically, hypercalcemia induced by high-dose vitamin D can increase the risk of arrhythmia from digoxin.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and digoxin concurrently.

Likelihood Possible Evidence D
Diltiazem (Cardizem, Others)

Theoretically, hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of diltiazem for arrhythmia.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically this could also occur with diltiazem. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and diltiazem concurrently.

Likelihood Probable Evidence B
Thiazide Diuretics

Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.
Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently. This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily.

Likelihood Probable Evidence D
Verapamil (Calan, Others)

Hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of verapamil for arrhythmia.
Hypercalcemia due to high doses of vitamin D can reduce the effectiveness of verapamil in atrial fibrillation. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and verapamil concurrently.

Likelihood Probable Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
There is some concern that vitamin D might induce CYP3A4. In vitro research suggests that vitamin D induces CYP3A4 transcription. Additionally, observational research has found that increased UV light exposure and serum vitamin D levels are associated with decreased serum levels of CYP3A4 substrates such as tacrolimus and sirolimus, while no association between UV light exposure or vitamin D levels and levels of mycophenolic acid, a non-CYP3A4 substrate, was found. A small, low-quality clinical study shows that taking vitamin D reduces levels of the CYP3A4 substrate atorvastatin and its active metabolites by up to 55%; however, the clinical effects of atorvastatin were not reduced. While researchers theorized that vitamin D might induce CYP3A4, this proposed mechanism was not specifically studied.

Likelihood Possible Evidence D

Acetyl-L-Carnitine4 drug types · 203 drugs

Acenocoumarol (Sintrom)

Theoretically, acetyl-L-carnitine might increase the anticoagulant effects of acenocoumarol.
L-carnitine, the parent compound of acetyl-L-carnitine, might enhance the anticoagulant effects of acenocoumarol, an oral anticoagulant that is similar to warfarin, but shorter-acting. There are at least two case reports of INR elevation when L-carnitine was taken with acenocoumarol. 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. It is unclear if such an interaction would also occur with acetyl-L-carnitine.

Likelihood Possible Evidence D
Serotonergic Drugs

Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Animal research shows that acetyl-L-carnitine can increase levels of serotonin in the brain.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, acetyl-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. It is unclear if such an interaction would occur with acetyl-L-carnitine.

Likelihood Probable Evidence B
Warfarin (Coumadin)

Theoretically, acetyl-L-carnitine might increase the anticoagulant effects of warfarin.
L-carnitine, the parent compound of acetyl-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 acetyl-L-carnitine and warfarin.

Likelihood Possible Evidence D

Chromium5 drug types · 178 drugs

Antidiabetes Drugs

Theoretically, chromium may have additive effects with antidiabetic agents and increase the risk of hypoglycemia.
Some research shows that taking chromium might lower blood glucose levels, especially in patients with poorly controlled type 2 diabetes.

Likelihood Possible Evidence A
Insulin

Theoretically, concomitant use of chromium and insulin might increase the risk of hypoglycemia.
In clinical research, chromium has been shown to increase insulin sensitivity,

Likelihood Possible Evidence B
Levothyroxine (Synthroid, Others)

Chromium might bind levothyroxine in the intestinal tract and decrease levothyroxine absorption.
Clinical research in healthy volunteers shows that taking chromium picolinate 1000 mcg with levothyroxine 1 mg decreases serum levels of levothyroxine by 17% when compared to taking levothyroxine alone. Advise patients to take levothyroxine at least 30 minutes before or 3-4 hours after taking chromium.

Likelihood Probable Evidence B
Aspirin

Theoretically, aspirin might increase chromium absorption.
Animal research suggests that aspirin may increase chromium absorption and chromium levels in the blood.

Likelihood Possible Evidence D
Nonsteroidal Anti-Inflammatory Drugs (Nsaids)

NSAIDs might increase chromium levels in the body.
Drugs that are prostaglandin inhibitors, such as NSAIDs, seem to increase chromium absorption and retention.

Likelihood Possible Evidence D

Riboflavin1 drug type · 20 drugs

Tetracycline Antibiotics

Theoretically, taking riboflavin with tetracycline antibiotics may decrease the potency of these antibiotics.
In vitro research suggests that riboflavin may inhibit the potency of tetracycline antibiotics. It is not clear if this effect is clinically significant, as this interaction has not been reported in humans.

Likelihood Possible Evidence D
The maker

Brand information

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

ILN Iron Labs Nutrition

See all ILN Iron Labs Nutrition products
Name
Euro Nutrition Ltd
Street Address
Discovery Court, 551-553 Wallisdown Rd
City
Poole
State
UK
ZipCode
BH12 5AG
Pharmacist Counseling Corner

Carnitine 2000 mg by ILN Iron Labs Nutrition: Common Questions

Does Carnitine 2000 mg by ILN Iron Labs Nutrition interact with any medications?
Yes. Based on its ingredients, Carnitine 2000 mg has a known interaction with 1,279 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Carnitine 2000 mg contains 6 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm pregnant or breastfeeding?
Most ingredients are generally considered safe at recommended amounts during pregnancy and breastfeeding—riboflavin, biotin, niacin, and vitamin D are actually needed. However, chromium and acetyl-L-carnitine have cautions or insufficient data in pregnancy and breastfeeding respectively. Talk with your doctor or pharmacist before starting this product if you're pregnant or nursing.
What's acetyl-L-carnitine and what does it do?
Acetyl-L-carnitine is a compound that supports energy production inside your cells. The data we hold shows it's Possibly Effective for age-related cognitive decline, Alzheimer disease, diabetic nerve pain, depression, and alcohol use disorder, though the evidence is still developing.
Why would my urine turn bright yellow?
That's the riboflavin in this product. High doses of riboflavin are cleared through your urine and turn it bright yellow—it's harmless and will go away once you stop taking it or your body adjusts.
Is this safe to take long-term?
Most ingredients are well tolerated at recommended doses. Riboflavin, biotin, niacin, and vitamin D at normal amounts are generally safe long-term. Chromium is usually well tolerated at typical doses, but the safety notes caution that high or long-term doses may pose risks. Acetyl-L-carnitine is generally well tolerated short-term, but long-term safety is not fully established—ask your pharmacist about your specific situation.
Can this help with weight loss or energy?
Acetyl-L-carnitine supports cellular energy production, which is why it's in this product. However, we don't have effectiveness data showing this product specifically improves energy or weight loss. If that's your goal, talk with your doctor or pharmacist about whether it's right for you.
What side effects might I notice?
Common side effects from these ingredients can include nausea, diarrhea, headache, and insomnia. Riboflavin may cause bright yellow urine. Niacin can cause flushing and gastrointestinal upset, especially at higher doses. Acetyl-L-carnitine may cause dry mouth or reduced appetite. Most of these are mild, but talk with your pharmacist if anything bothers you.

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

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Carnitine 2000 mg label
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The Full Monographs Behind Carnitine 2000 mg’s Ingredients

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

Herb & supplement monograph

Riboflavin

Interacts with 20 drugs

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally very safe at typical doses, and the stro...

Read the full Riboflavin 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

Chromium

Interacts with 178 drugs

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control in certain people with type 2 diabetes, b...

Read the full Chromium monograph →
Herb & supplement monograph

Niacin

Interacts with 727 drugs

Niacin (vitamin B3) is an essential nutrient your body needs for energy and metabolism, and deficiency is uncommon in most developed countries. Prescription-strength niacin has been used to...

Read the full Niacin monograph →
Herb & supplement monograph

Vitamin D

Interacts with 715 drugs

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people, especially those with low sun exposure,...

Read the full Vitamin D monograph →
Herb & supplement monograph

Acetyl-l-carnitine

Interacts with 203 drugs

Acetyl-L-carnitine is a form of the amino acid carnitine that the body uses to help produce energy in cells. It is most studied for nerve pain and memory-related conditions, though the evide...

Read the full Acetyl-l-carnitine monograph →
Sources

Sources & How We Checked

Carnitine 2000 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 176 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.

Riboflavin 5 references
  1. Schoenen J, Jacquy J, Lenaerts M. Effectiveness of high-dose riboflavin in migraine prophylaxis. A randomized controlled trial. Neurology 1998;50:466-70. PubMed
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Leeson LJ, Weidenheimer JF. Stability of tetracycline and riboflavin. J Pharm Sci. 1969;58(3):355-7. PubMed
  4. MacLennan, S. C., Wade, F. M., Forrest, K. M., Ratanayake, P. D., Fagan, E., and Antony, J. High-dose riboflavin for migraine prophylaxis in children: a double-blind, randomized, placebo-controlled trial. J Child Neurol. 2008;23(11):1300-1304.
  5. Dietary reference intakes (DRIs): estimated average requirements. Food and Nutrition Board, Institute of Medicine, National Academics. https://www.nal.usda.gov/sites/default/files/fnic_uploads//recommended_intakes_individuals.pdf Accessed July 24, 2017.

See these in context on the Riboflavin monograph →

Biotin 4 references
  1. Debourdeau PM, Djezzar S, Estival JL, et al. Life-threatening eosinophilic pleuropericardial effusion related to vitamins B5 and H. Ann Pharmacother 2001;35:424-6. DOI
  2. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  3. Mock DM, Quirk JG, Mock NI. Marginal biotin deficiency during normal pregnancy. Am J Clin Nutr 2002;75:295-9. PubMed
  4. Sedel F, Papeix C, Bellanger A, Touitou V, Lebrun-Frenay C, Galanaud D, et al. High doses of biotin in chronic progressive multiple sclerosis: a pilot study.Mult Scler Relat Disord. 2015;4(2):159-69. doi: 10.1016/j.msard.2015.01.005. PubMed

See these in context on the Biotin monograph →

Chromium 53 references
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  2. Urberg M, Zemel MB. Evidence for synergism between chromium and nicotinic acid in the control of glucose tolerance in elderly humans. Metabolism 1987;36:896-9. PubMed
  3. Mohamedshah FY, Moser-Veillon PB, Yamini S, et al. Distribution of a stable isotope of chromium (53Cr) in serum, urine, and breast milk in lactating women. Am J Clin Nutr 1998;67:1250-5. PubMed
  4. Wasser WG, Feldman NS, D'Agati VD. Chronic renal failure after ingestion of over-the-counter chromium picolinate. [letter]. Ann Intern Med 1997;126:410. PubMed
  5. Mertz W. Interaction of chromium with insulin: a progress report. Nutr Rev 1998;56:174-7. PubMed
  6. Anderson RA. Chromium, glucose intolerance and diabetes. J Am Coll Nutr 1998;17:548-55. PubMed
  7. McLeod MN, Gaynes BN, Golden RN. Chromium potentiation of antidepressant pharmacotherapy for dysthymic disorder in 5 patients. J Clin Psych 1999;60:237-40. PubMed
  8. Fowler JF Jr. Systemic contact dermatitis caused by oral chromium picolinate. Cutis 2000;65:116. DOI
  9. Trent LK, Thieding-Cancel D. Effects of chromium picolinate on body composition. J Sports Med Phys Fitness 1995;35:273-80.
  10. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  11. Rabinovitz H, Friedensohn A, Leibovitz A, et al. Effect of chromium supplementation on blood glucose and lipid levels in type 2 diabetes mellitus elderly patients. Int J Vitam Nutr Res 2004;74:178-82. PubMed
  12. Lanca S, Alves A, Vieira AI, et al. Chromium-induced toxic hepatitis. Eur J Intern Med 2002;13:518-20. PubMed
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  16. Mouser JF, Hak EB, Helms RA, et al. Chromium and zinc concentrations in pediatric patients receiving long-term parenteral nutrition. Am J Health Syst Pharm 1999;56:1950-6. PubMed
  17. Stevens T, Qadri A, Zein NN. Two patients with acute liver injury associated with use of the herbal weight-loss supplement hydroxycut. Ann Intern Med 2005;142:477-8. PubMed
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  22. John-Kalarickal J, Pearlman G, Carlson HE. New medications which decrease levothyroxine absorption. Thyroid 2007;17:763-5. PubMed
  23. Yazaki Y, Faridi Z, Ma Y, et al. A pilot study of chromium picolinate for weight loss. J Altern Complement Med 2010;16:291-9. PubMed
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  25. Young P, Turiansky G, Bonner M, and et al. Acute generalized exanthematous pustulosis induced by chromium picolinate. J.Am Acad.Dermatol. 1999;41(5 Pt 2):820-823. PubMed
  26. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Lung cancer among workers in chromium chemical production. Am J Ind.Med 2000;38(2):115-126. DOI
  27. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Clinical findings of irritation among chromium chemical production workers. Am J Ind.Med 2000;38(2):127-131. PubMed
  28. Pittler, M. H. and Ernst, E. Dietary supplements for body-weight reduction: a systematic review. Am.J.Clin Nutr. 2004;79(4):529-536. PubMed
  29. Pei, D., Hsieh, C. H., Hung, Y. J., Li, J. C., Lee, C. H., and Kuo, S. W. The influence of chromium chloride-containing milk to glycemic control of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial. Metabolism 2 PubMed
  30. Hisatomi, K., Ishii, H., Hashiguchi, K., Seki, M., Ide, M., Sugiyama, K., Ishimoto, H., Nakayama, S., Mukae, H., and Kohno, S. Interstitial pneumonia caused by inhalation of fumes of nickel and chrome. Respirology. 2006;11(6):814-817. PubMed
  31. Kleefstra, N., Houweling, S. T., Bakker, S. J., Verhoeven, S., Gans, R. O., Meyboom-de Jong, B., and Bilo, H. J. Chromium treatment has no effect in patients with type 2 diabetes in a Western population: a randomized, double-blind, placebo-controlled tri DOI
  32. Parsons, A., Ingram, J., Inglis, J., Aveyard, P., Johnstone, E., Brown, K., Franklin, M., and Bermudez, I. A proof of concept randomised placebo controlled factorial trial to examine the efficacy of St John's wort for smoking cessation and chromium to pr
  33. Bagdon RE and Hazen RE. Skin permeation and cutaneous hypersensitivity as a basis for making risk assessments of chromium as a soil contaminant. Environ.Health Perspect. 1991;92:111-119. PubMed
  34. Bharmal, S. V., Moyes, V., Ahmed, S., and Grossman, A. Hypoglycaemia: possible mediation by chromium salt medication. Hormones.(Athens.) 2010;9(2):181-183. PubMed
  35. Krol, E., Krejpcio, Z., Byks, H., Bogdanski, P., and Pupek-Musialik, D. Effects of chromium brewer's yeast supplementation on body mass, blood carbohydrates, and lipids and minerals in type 2 diabetic patients. Biol.Trace Elem.Res. 2011;143(2):726-737.
  36. Unisa, S., Jagannath, P., Dhir, V., Khandelwal, C., Sarangi, L., and Roy, T. K. Population-based study to estimate prevalence and determine risk factors of gallbladder diseases in the rural Gangetic basin of North India. HPB (Oxford) 2011;13(2):117-125. PubMed
  37. Noda, S., Asano, Y., and Sato, S. Lichen planus in a patient with long-term exposure to chrome. Eur.J.Dermatol. 2011;21(3):417-418. PubMed
  38. Xiang, J., Sun, Z., and Huan, J. N. Intensive chromic acid burns and acute chromium poisoning with acute renal failure. Chin Med.J.(Engl.) 7-5-2011;124(13):2071-2073.
  39. Chhabra, D., Oda, K., Jagannath, P., Utsunomiya, H., Takekoshi, S., and Nimura, Y. Chronic heavy metal exposure and gallbladder cancer risk in India, a comparative study with Japan. Asian Pac.J.Cancer Prev. 2012;13(1):187-190. PubMed
  40. Huszonek, J. Over-the-counter chromium picolinate. Am J Psychiatry 1993;150(10):1560-1561. PubMed
  41. Bunner S and McGinnis R. Chromium-induced hypoglycemia. Psychosomatics 1998;39(3):298-299. PubMed
  42. Martin, W. R. and Fuller, R. E. Suspected chromium picolinate-induced rhabdomyolysis. Pharmacotherapy 1998;18(4):860-862. DOI
  43. Proctor, D. M., Fredrick, M. M., Scott, P. K., Paustenbach, D. J., and Finley, B. L. The prevalence of chromium allergy in the United States and its implications for setting soil cleanup: a cost-effectiveness case study. Regul.Toxicol Pharmacol 1998;28(1 PubMed
  44. De Marchi S, Cecchin E, De Marchi SU. Systemic allergic dermatitis resulting from oral administration of chromium with a food supplement. Contact Dermatitis 2014;70(2):123-5. PubMed
  45. Hedberg YS, Gumulka M, Lind ML, Matura M, Lidén C. Severe occupational chromium allergy despite cement legislation. Contact Dermatitis. 2014;70(5):321-3. PubMed
  46. Thyssen JP, Jellesen MS, Møller P, Menné T, Johansen JD. Allergic chromium dermatitis from wearing 'chromium-free' footwear. Contact Dermatitis 2014;70(3):185-7. PubMed
  47. Liu Y, Cotillard A, Vatier C, et al. A Dietary Supplement Containing Cinnamon, Chromium and Carnosine Decreases Fasting Plasma Glucose and Increases Lean Mass in Overweight or Obese Pre-Diabetic Subjects: A Randomized, Placebo-Controlled Trial. PLoS One.
  48. Jamilian M, Asemi Z. Chromium Supplementation and the Effects on Metabolic Status in Women with Polycystic Ovary Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial. Ann Nutr Metab. 2015;67(1):42-8. PubMed
  49. Guimarães MM, Carvalho AC, Silva MS. Effect of chromium supplementation on the glucose homeostasis and anthropometry of type 2 diabetic patients: Double blind, randomized clinical trial: Chromium, glucose homeostasis and anthropometry. J Trace Elem Med Bi PubMed
  50. Paiva AN, Lima JG, Medeiros AC, et al. Beneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study. J Trace Elem Med Biol. 2015;32:66-72. PubMed
  51. Yin RV, Phung OJ. Effect of chromium supplementation on glycated hemoglobin and fasting plasma glucose in patients with diabetes mellitus. Nutr J. 2015;14:14. PubMed
  52. Jamilian M, Zadeh Modarres S, Amiri Siavashani M, et al. The influences of chromium supplementation on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome women candidate for in vitro fertilizati
  53. Alinaghi F, Thyssen JP, Zachariae C, Johansen JD. No immediate effect of regulatory reduction of chromium in leather among adult patients with chromium allergy. Contact Dermatitis 2021;85(5):514-522. PubMed

See these in context on the Chromium monograph →

Niacin 66 references
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  66. Nawaz N, Mistretta T, Karime C, Lewis J, Wolf E. Cholestatic Drug-Induced Liver Injury in a Patient Taking High-Dose Niacin for Hyperlipidemia. J Investig Med High Impact Case Rep 2024;12:23247096231224349. PubMed

See these in context on the Niacin monograph →

Vitamin D 26 references
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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.

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