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Dietary supplement

Acetyl L-Carnitine 500 mg Ingredients & Drug Interactions

by Swanson

Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Acetyl L-Carnitine 500 mg is a dietary supplement by Swanson with 1 active ingredient. Its ingredients are commonly taken for memory and cognitive support, nerve pain (neuropathy), energy and fatigue.Based on those ingredients, 203 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Acetyl L-Carnitine HCl. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Acetyl L-Carnitine 500 mg by Swanson

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: acetyl L-carnitine HCl, a form of L-carnitine, at 500 mg per capsule. The capsule also holds inactive ingredients — hypromellose, microcrystalline cellulose, magnesium stearate, and silica — which are binders and fillers that help form and deliver the capsule.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Energizes mind and promotes cognitive health.
  • We looked for evidence on: Age-related cognitive decline, Alzheimer disease, Attention deficit-hyperactivity disorder (ADHD), Chronic fatigue syndrome (CFS), Cancer-related fatigue, Multiple sclerosis-related fatigue — and 3 related terms.
  • The strongest evidence on file: Acetyl-l-carnitine is rated "Possibly Effective" for Age-related cognitive decline (Natural Medicines).
  • Also on file: Acetyl-l-carnitine is rated "Possibly Effective" for Alzheimer disease.
  • Also on file: Acetyl-l-carnitine is rated "Insufficient Reliable Evidence To Rate" for Attention deficit-hyperactivity disorder (ADHD), Cancer-related fatigue, Chronic fatigue syndrome (CFS), Multiple sclerosis-related fatigue.

Acetyl-L-carnitine is rated possibly effective for several conditions in our data: age-related cognitive decline, Alzheimer disease, alcohol use disorder, diabetic nerve pain (neuropathy), and depression. That means there's some evidence it may help, but it's not yet conclusive.

The strength of evidence varies by condition, so talk with your doctor about whether it might fit your situation.

The evidence, ingredient by ingredient 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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Acetyl-L-carnitine is generally well tolerated when taken by mouth short-term, but long-term safety hasn't been fully studied. Common side effects include agitation, dry mouth, headache, insomnia, and reduced appetite.

Some people report a fishy odor in their urine, breath, or sweat. Gastrointestinal upset — nausea, vomiting, diarrhea, constipation — can occur, though it doesn't happen more often than with placebo in most trials.

In people with Alzheimer disease, psychiatric side effects like depression, mania, confusion, or aggression have been reported, though it's unclear whether acetyl-L-carnitine caused them or the condition itself.

Side effects, ingredient by ingredient 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?
  • 1 of the 1 matched ingredient can interact with medications — Acetyl-l-carnitine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 203 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 you start, double-check with your pharmacist if you take serotonergic drugs like antidepressants or migraine medications (Moderate risk), blood thinners such as warfarin or acenocoumarol (Moderate risk), or thyroid hormone replacement (Moderate risk). No interactions are documented for the ingredient we could check beyond these categories, but that doesn't guarantee none exist — your pharmacist can search your full medication list on this page.

Check your own medication Run your meds through the checker above

The bottom line

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

Acetyl-L-carnitine may help with cognitive decline, Alzheimer disease, nerve pain, depression, or alcohol use disorder, but evidence is still building. If you take serotonergic drugs (antidepressants, migraine medications), blood thinners (warfarin, acenocoumarol), or thyroid hormone, you need to check with your pharmacist first.

It's generally well tolerated short-term, but long-term safety isn't established yet.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 19, 2022.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Acetyl L-Carnitine 500 mg, straight from the product label.

Brand Swanson
Barcode (UPC) 087614116495
Net contents 100 Veggie Capsule(s)
Market status On market
Date entered into DSLD May 19, 2022
DSLD ID 264942
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses 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 Acetyl L-Carnitine 500 mg by Swanson, 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 Veggie Capsule(s)
Maximum serving Sizes:
1 Veggie Capsule(s)
Servings per container
100
UPC/BARCODE
087614116495
IngredientAmount% DV
Acetyl L-Carnitine HCl500 mg--

Other ingredients: Hypromellose, Microcrystalline Cellulose, Magnesium Stearate, Silica

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.
General Statements

swanson.com or call 1-800-437-4148

Science-Backed Quality since 1969

Formulation

Energizes the mind and promotes concentration Passes through the blood-brain barrier to support cognitive health & optimal brain function

Brain and Nervous System Health

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take one veggie capsule one to two times per day with water.

Precautions

Warning: For adults only.

Consult your healthcare provider before using this or any product if you are pregnant or nursing, taking medication or have a medical condition.

Keep out of reach of children.

Do not use if seal is broken.

Storage

Store in a cool, dry place.

FDA Disclaimer Statement

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

FDA Statement of Identity

Dietary Supplement

See for yourself

Acetyl L-Carnitine 500 mg by Swanson label

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

What’s inside

The Ingredients in Acetyl L-Carnitine 500 mg by Swanson

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Veggie Capsule(s) Dosage formCapsule Servings per container100 Amounts shown are per serving.

Acetyl L-Carnitine HCl

Interacts with
203 drugs
500 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 HCl monograph & interactions

Other (inactive) ingredients: Hypromellose, Microcrystalline Cellulose, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.

Interaction report

Acetyl L-Carnitine 500 mg by Swanson Drug Interactions

Want to check YOUR meds against Acetyl L-Carnitine 500 mg?

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

Go to the checker
203Drugs
203 Moderate

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in Acetyl L-Carnitine 500 mg with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Acetyl L-Carnitine HCl4 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
The maker

Brand information

Manufacturer and brand details for Acetyl L-Carnitine 500 mg, from the product label.

Swanson

See all Swanson products
Name
Swanson Health Products
City
Fargo
State
ND
ZipCode
58104
Phone Number
1-800-437-4148
Web Address
swanson.com
Pharmacist Counseling Corner

Acetyl L-Carnitine 500 mg by Swanson: Common Questions

Does Acetyl L-Carnitine 500 mg by Swanson interact with any medications?
Yes. Based on its ingredients, Acetyl L-Carnitine 500 mg has a known interaction with 203 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Acetyl L-Carnitine 500 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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.
What is acetyl-L-carnitine, and what does it do in the body?
Acetyl-L-carnitine is a form of L-carnitine, a compound involved in energy production and brain function. Our data shows it's possibly effective for cognitive decline, Alzheimer disease, depression, diabetic nerve pain, and alcohol use disorder — but the evidence isn't conclusive for any of them yet.
Can I take this if I'm on an antidepressant?
Not without checking with your pharmacist first. Acetyl-L-carnitine may theoretically increase serotonin levels in your brain, which could raise the risk of serotonin syndrome or related side effects when combined with serotonergic drugs like antidepressants. This is rated Moderate severity, so it needs a conversation with your pharmacist before you start.
What are the most common side effects?
Agitation, dry mouth, headache, insomnia, and reduced appetite are the main ones reported. Some people notice a fishy smell in their urine, breath, or sweat. Nausea, vomiting, diarrhea, and constipation can happen, though they don't occur more often than with placebo in most studies.
Is it safe to take long-term?
Short-term use is generally well tolerated, but long-term safety hasn't been fully established in the data we hold. Talk with your doctor about how long you plan to take it and whether monitoring is needed.
Can I take this while pregnant or breastfeeding?
There isn't enough reliable safety information to know either way during pregnancy, and safety while breastfeeding is unknown — avoiding it is the safer choice unless your doctor advises otherwise. Talk with your doctor or pharmacist before using it if you're pregnant, trying to become pregnant, or breastfeeding.
Will this interfere with my thyroid medication?
Yes, possibly. Acetyl-L-carnitine might theoretically decrease how well thyroid hormone replacement works by blocking the hormone from entering cells properly. This is rated Moderate severity, so check with your pharmacist before starting if you're on thyroid hormone therapy.

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.

Acetyl L-Carnitine 500 mg label
Sources

Sources & How We Checked

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

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 22 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.

Acetyl-l-carnitine 22 references
  1. Thal LJ, Carta A, Clarke WR, et al. A 1-year multicenter placebo-controlled study of acetyl-L-carnitine in patients with Alzheimer's Disease. Neurology 1996;47:705-11. PubMed
  2. Sano M, Bell K, Cote L, et al. Double-blind parallel design pilot study of acetyl levocarnitine in patients with Alzheimer's Disease. Arch Neurol 1992;49:1137-41. PubMed
  3. Spagnoli A, Lucca U, Menasce G, et al. Long-term acetyl-L-carnitine treatment in Alzheimer's Disease. Neurology 1991;41:1726-32. PubMed
  4. Brooks JO 3rd, Yesavage JA, Carta A, Bravi D. Acetyl L-carnitine slows decline in younger patients with Alzheimer's disease: a reanalysis of a double-blind, placebo-controlled study using the trilinear approach. Int Psychoger 1998;10:193-203. PubMed
  5. Pettegrew JW, Klunk WE, Panchalingam K, et al. Clinical and neurochemical effects of acetyl-L-carnitine in Alzheimer's disease. Neurobiol Aging 1995;16:1-4. PubMed
  6. Rai G, Wright G, Scott L, et al. Double-blind, placebo controlled study of acetyl-l-carnitine in patients with Alzheimer's dementia. Curr Med Res Opin 1990;11:638-47. PubMed
  7. Benvenga S, Ruggeri RM, Russo A, et al. Usefulness of L-carnitine, a naturally occurring peripheral antagonist of thyroid hormone action, in iatrogenic hyperthyroidism: a randomized, double-blind, placebo-controlled clinical trial. J Clin Endocrinol Meta
  8. Montgomery SA, Thal LJ, Amrein R. Meta-analysis of double blind randomized controlled clinical trials of acetyl-L-carnitine versus placebo in the treatment of mild cognitive impairment and mild Alzheimer's disease. Int Clin Psychopharmacol 2003;18:61-71.. PubMed
  9. Martinez E, Domingo P, Roca-Cusachs A. Potentiation of acenocoumarol action by L-carnitine. J Intern Med 1993;233:94.
  10. Hudson S, Tabet N. Acetyl-L-carnitine for dementia. Cochrane Database Syst Rev 2003;2:CD003158.. PubMed
  11. Bachmann HU, Hoffmann A. Interaction of food supplement L-carnitine with oral anticoagulant acenocoumarol. Swiss Med Wkly 2004;134:385. PubMed
  12. De Grandis D, Minardi C. Acetyl-L-carnitine (levacecarnine) in the treatment of diabetic neuropathy. A long-term, randomised, double-blind, placebo-controlled study. Drugs R D 2002;3:223-31. PubMed
  13. 12761 Benvenga S, Amato A, Calvani M, Trimarchi F. Effects of carnitine on thyroid hormone action. Ann N Y Acad Sci 2004;1033:158-67. PubMed
  14. Sima AAF, Calvani M, Mehra M, et al. Acetyl-L-carnitine improves pain, nerve regeneration, and vibratory perception in patients with chronic diabetic neuropathy: An analysis of two randomized, placebo-controlled trials. Diabetes Care 2005;28:89-94.
  15. Youle, M. and Osio, M. A double-blind, parallel-group, placebo-controlled, multicentre study of acetyl L-carnitine in the symptomatic treatment of antiretroviral toxic neuropathy in patients with HIV-1 infection. HIV.Med. 2007;8(4):241-250.
  16. Brennan BP, Jensen JE, Hudson JI, Coit CE, Beaulieu A, Pope HG Jr, Renshaw PF, Cohen BM. A placebo-controlled trial of acetyl-L-carnitine and a-lipoic acid in the treatment of bipolar depression. J Clin Psychopharmacol. 2013 Oct;33(5):627-35.
  17. Ledinek AH, Sajko MC, Rot U. Evaluating the effects of amantadin, modafinil and acetyl-L-carnitine on fatigue in multiple sclerosis--result of a pilot randomized, blind study. Clin Neurol Neurosurg. 2013 Dec;115 Suppl 1:S86-9. PubMed
  18. Martinotti G, Andreoli S, Reina D, Di Nicola M, Ortolani I, Tedeschi D, Fanella F, Pozzi G, Iannoni E, D'Iddio S, Prof LJ. Acetyl-l-Carnitine in the treatment of anhedonia, melancholic and negative symptoms in alcohol dependent subjects. Prog Neuropsychop PubMed
  19. Baek SM, Zheng R, Seo EJ, Hwang DY, Kim BH. Pharmacokinetic comparisons of two acetyl-L-carnitine formulations in healthy Korean volunteers. Int J Clin Pharmacol Ther. 2015;53(11):980-6. PubMed
  20. Goodison G, Overeem K, de Monte V, Siskind D. Mania associated with self-prescribed acetyl-l-carnitine in a man with bipolar I disorder. Australas Psychiatry. 2017;25(1):13-4.
  21. Bruno A, Pandolfo G, Crucitti M, Lorusso S, Zoccali RA, Muscatello MR. Acetyl-L-Carnitine Augmentation of Clozapine in Partial-Responder Schizophrenia: A 12-Week, Open-Label Uncontrolled Preliminary Study. Clin Neuropharmacol. 2016;39(6):277-80. PubMed
  22. Veronese N, Stubbs B, Solmi M, Ajnakina O, Carvalho AF, Maggi S. Acetyl-L-Carnitine Supplementation and the Treatment of Depressive Symptoms: A Systematic Review and Meta-Analysis. Psychosom Med. 2018;80(2):154-9. PubMed

See these in context on the Acetyl-l-carnitine monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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