Optimized Carnitine Ingredients & Drug Interactions
What is this page for?
First and foremost: checking Optimized Carnitine 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
Optimized Carnitine is a dietary supplement by Life Extension with 3 active ingredients. 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 Arginate Dihydrochloride, Glycine Propionyl L-Carnitine Hydrochloride. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Optimized Carnitine by Life Extension
Ask about any prescription or over-the-counter medication and we check it for interactions with Optimized Carnitine by Life Extension — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Optimized Carnitine by Life Extension
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.
What’s inside
Full disclosure
Optimized Carnitine contains three active ingredients, all forms of L-carnitine: acetyl-L-carnitine arginate dihydrochloride, acetyl-L-carnitine hydrochloride, and glycine propionyl-L-carnitine hydrochloride. L-carnitine is a compound that plays a role in how your body uses energy.
The product also contains inactive ingredients—cellulose, stearate, and silica—which are fillers and binders that hold the capsule together.
Does it work?
Insufficient evidence
The acetyl-L-carnitine ingredients are rated possibly effective for age-related cognitive decline, Alzheimer disease, alcohol use disorder, diabetic nerve damage, and depression based on the data we hold. The propionyl-L-carnitine ingredient is rated possibly effective for ulcerative colitis, congestive heart failure, and angina.
These ratings mean there's evidence suggesting a benefit, but the research isn't conclusive enough to call them proven.
How safe is it?
Well-documented data
Acetyl-L-carnitine is generally well tolerated in the short term, though long-term safety isn't fully established. The most common side effects are agitation, dry mouth, headache, insomnia, and reduced appetite; some people report a fishy odor in urine, breath, or sweat.
Nausea, vomiting, diarrhea, and other digestive complaints can occur but don't typically happen more often than with placebo. Propionyl-L-carnitine is also well tolerated but may cause diarrhea, stomach pain, nausea, or vomiting; one trial reported more bronchitis and back pain compared to placebo.
There isn't enough reliable safety information during pregnancy, so it's best avoided unless your doctor advises otherwise. Safety while breastfeeding is unknown—avoiding it is the safer choice.
Meds to double-check
Moderate interaction found
Before you start Optimized Carnitine, check with your pharmacist if you take blood thinners like warfarin or acenocoumarol (Moderate risk), antidepressants or serotonergic medications (Moderate risk), or thyroid hormone replacement (Moderate risk). Use the medication search tool on this page to look up your specific drugs.
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 is for people interested in cognitive support, heart health, or managing conditions like angina or inflammatory bowel disease. If you take blood thinners, antidepressants, or thyroid replacement, talk to your pharmacist before starting.
Long-term safety data is limited, so discuss this with your doctor, especially if you're pregnant or breastfeeding.
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
General information
Key facts about Optimized Carnitine, straight from the product label.
| Brand | Life Extension |
|---|---|
| Barcode (UPC) | 737870201861 |
| Net contents | 60 Vegetarian Capsule(s) |
| Market status | On market |
| Date entered into DSLD | May 21, 2025 |
| DSLD ID | 328611 |
| Product type | Non-nutrient/non-botanical |
| Supplement form | Capsule |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free |
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 Optimized Carnitine by Life Extension, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Acetyl L-Carnitine Arginate Dihydrochloride | 300 mg | -- |
| Acetyl L Carnitine Hydrochloride | 800 mg | -- |
| Glycine Propionyl L-Carnitine Hydrochloride | 300 mg | -- |
Other ingredients: Cellulose, Stearate, Silica
Tap any ingredient to jump to its full detail below.
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
Scan for product info
Precautions
Read the entire label and follow the directions carefully prior to use.
Warnings: Do not exceed recommended dose. Do not purchase if outer seal is broken or damaged.
When using nutritional supplements, please consult with your physician if you are undergoing treatment for a medical condition or if you are pregnant or lactating.
To report a serious adverse event or obtain product information, contact 1-866-280-2852.
Suggested/Recommended/Usage/Directions
Directions: Take two (2) capsules, once or twice daily, or as recommended by a healthcare practitioner. This product can be taken on an empty stomach with water or juice in the morning in divided doses or all at once.
Storage
Store tightly closed in a cool, dry place.
Formulation
Gluten free Non GMO Le certified
Promotes cellular energy production
Seals/Symbols
Non GMO Le certified
FDA Statement of Identity
Dietary Supplement
FDA Disclaimer Statement
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Optimized Carnitine by Life Extension label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Optimized Carnitine by Life Extension
These are the 3 active ingredients this product is made of. Select any to open its full monograph.
Serving size2 Vegetarian 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.
Acetyl L-Carnitine Arginate Dihydrochloride
Interacts with203 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 mem...
Acetyl L-Carnitine Arginate Dihydrochloride monograph & interactionsAcetyl L Carnitine Hydrochloride
Interacts with203 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 mem...
Acetyl L Carnitine Hydrochloride monograph & interactionsGlycine Propionyl L-Carnitine Hydrochloride
Interacts with19 drugs
Propionyl-l-carnitine is a form of the amino acid derivative carnitine that the body uses to help turn fat into energy, and it is studied mostly for c...
Glycine Propionyl L-Carnitine Hydrochloride monograph & interactionsOther (inactive) ingredients: Cellulose, Stearate, Silica. These complete the product’s ingredient list but are not active constituents.
Optimized Carnitine by Life Extension Drug Interactions
HelloPharmacist Interaction Report
Optimized Carnitine by Life Extension contains acetyl-L-carnitine and propionyl-L-carnitine, both of which interact with several medication types.
The most serious interactions are Moderate in severity.
Read the full breakdown — every affected drug type, severity by severity
The acetyl-L-carnitine ingredients can increase serotonin levels in the brain and theoretically raise the risk of serotonergic side effects—including serotonin syndrome and cerebral blood vessel constriction—when combined with serotonergic drugs (antidepressants, certain pain relievers, and similar medications). Both acetyl-L-carnitine forms and the propionyl-L-carnitine ingredient may increase the blood-thinning effects of warfarin and acenocoumarol (blood thinners used to prevent clots).
All three active ingredients can theoretically decrease how well thyroid hormone replacement works by blocking thyroid hormone entry into cells.
Altogether, these interactions span 203 individual medications. Use the medication checker on this page to look up your exact prescriptions before starting this product.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Optimized Carnitine?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Optimized Carnitine interact with 203 drugs. Click any drug to see the details.
2 of the 3 ingredients in Optimized Carnitine interact with drugs. Each result below shows which ingredient is responsible. Acetyl L-Carnitine Arginate Dihydrochloride Glycine Propionyl L-Carnitine Hydrochloride
AcenocoumarolSintrom
How Acenocoumarol interacts with Optimized Carnitine — through 2 ingredients. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideAcenocoumarol (sintrom) Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the anticoagulant effects of acenocoumarol.
Read the full Acetyl L Carnitine Hydrochloride + Acenocoumarol interactionGlycine Propionyl L-carnitine HydrochlorideAcenocoumarol (sintrom) Moderate
Interaction Summary
Theoretically, propionyl-L-carnitine might increase the anticoagulant effects of acenocoumarol.
Read the full Glycine Propionyl L-carnitine Hydrochloride + Acenocoumarol interactionAcetaminophen, Chlorpheniramine Maleate, Dextromethorphan HbrVicks Formula 44M Cough, Cold & Flu Relief
How Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interactionAcetaminophen, Chlorpheniramine, Codeine, PhenylephrineColrex
How Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interactionAcetaminophen, Chlorpheniramine, DextromethorphanCoricidin II Extra Strength Cold and Flu
How Acetaminophen, Chlorpheniramine, Dextromethorphan interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Dextromethorphan interactionAcetaminophen, Chlorpheniramine, Dextromethorphan HydrobromideCoricidin HBP Maximum Strength Flu
How Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PhenylpropanolamineMulti Symptom Cold Relief
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PseudoephedrineChildren's Tylenol Cold Plus Cough, Tylenol Cold Ex Strength
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interactionAcetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, SalicylamideRhinogesic GG
How Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interactionAcetaminophen, Chlorpheniramine, PhenylephrineAlka-Seltzer PLUS, Histex SR, Protid
How Acetaminophen, Chlorpheniramine, Phenylephrine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Phenylephrine interactionAcetaminophen, Chlorpheniramine, Phenylephrine, SalicylamideRhinogesic, Rhinogesic JR
How Acetaminophen, Chlorpheniramine, Phenylephrine, Salicylamide interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Phenylephrine, Salicylamide interactionAcetaminophen, Chlorpheniramine, PhenylpropanolamineAlumadrine, Conex, Sinadrin Max Strength, Sinulin
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Phenylpropanolamine interactionAcetaminophen, Chlorpheniramine, Phenylpropanolamine, OpiumHista-Derfule
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Opium interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Opium interactionAcetaminophen, Chlorpheniramine, Phenylpropanolamine, PhenyltoloxamineNorel Plus
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Phenyltoloxamine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Phenyltoloxamine interactionAcetaminophen, Chlorpheniramine, PseudoephedrineAlka-Seltzer PLUS Liquid Gels, Children's Tylenol Cold, Codimal, Comtrex, Extra Strength Tylenol Allergy Sinus, Lorsin +3 more
How Acetaminophen, Chlorpheniramine, Pseudoephedrine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Chlorpheniramine, Pseudoephedrine interactionAcetaminophen, DextromethorphanTylenol Cough Ex Strength
How Acetaminophen, Dextromethorphan interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Dextromethorphan interactionAcetaminophen, Dextromethorphan, Doxylamine, PseudoephedrineVicks NyQuil
How Acetaminophen, Dextromethorphan, Doxylamine, Pseudoephedrine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Dextromethorphan, Doxylamine, Pseudoephedrine interactionAcetaminophen, Dextromethorphan, Guaifenesin, PhenylephrineConar-A
How Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine interactionAcetaminophen, Dextromethorphan, Guaifenesin, PhenylpropanolamineAnatuss
How Acetaminophen, Dextromethorphan, Guaifenesin, Phenylpropanolamine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Dextromethorphan, Guaifenesin, Phenylpropanolamine interactionAcetaminophen, Dextromethorphan, Guaifenesin, PseudoephedrineRobitussin Cold, Severe Cold, Suphedrine Cold/Cough
How Acetaminophen, Dextromethorphan, Guaifenesin, Pseudoephedrine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Dextromethorphan, Guaifenesin, Pseudoephedrine interactionAcetaminophen, Dextromethorphan, Phenylpropanolamine, PyrilamineTheracaps
How Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine interactionAcetaminophen, Dextromethorphan, PseudoephedrineAlka-Seltzer PLUS Flu Liquid Gels, Non Aspirin Cold Caps, Tylenol Cold, Tylenol Flu Daytime Ex Strength, Tylenol Flu Ex Strength
How Acetaminophen, Dextromethorphan, Pseudoephedrine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Dextromethorphan, Pseudoephedrine interactionAcetaminophen, MeperidineDemerol APAP
How Acetaminophen, Meperidine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Meperidine interactionAcetaminophen, Phenylephrine, ChlorpheniramineSuper Cold Tabs
How Acetaminophen, Phenylephrine, Chlorpheniramine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Acetaminophen, Phenylephrine, Chlorpheniramine interactionAlmotriptanAlmogran, Axert
How Almotriptan interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Almotriptan interactionAlosetronLotronex
How Alosetron interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Alosetron interactionAmitriptylineElavil
How Amitriptyline interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Amitriptyline interactionAmitriptyline, ChlordiazepoxideLimbitrol DS
How Amitriptyline, Chlordiazepoxide interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Amitriptyline, Chlordiazepoxide interactionAmitriptyline, PerphenazineEtrafon, Etrafon-A, Etrafon-Forte, Triavil
How Amitriptyline, Perphenazine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Amitriptyline, Perphenazine interactionAmoxapineAsendin
How Amoxapine interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Amoxapine interactionAmphetamine Aspartate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine SulfateAdderall, Adderall XR
How Amphetamine Aspartate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine Sulfate interacts with Optimized Carnitine — through 1 ingredient. Tap an ingredient for the detail:
Acetyl L Carnitine HydrochlorideSerotonergic Drugs Moderate
Interaction Summary
Theoretically, acetyl-L-carnitine might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders, when taken with serotonergic drugs.
Read the full Acetyl L Carnitine Hydrochloride + Amphetamine Aspartate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine Sulfate interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Optimized Carnitine 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.
Acetyl L-Carnitine Arginate Dihydrochloride
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.
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.
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.
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.
Glycine Propionyl L-Carnitine Hydrochloride
Acenocoumarol (Sintrom)
Theoretically, propionyl-L-carnitine might increase the anticoagulant effects of acenocoumarol.
L-carnitine, the parent compound of propionyl-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 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 propionyl-L-carnitine.
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 propionyl-L-carnitine.
Warfarin (Coumadin)
Theoretically, propionyl-L-carnitine might increase the anticoagulant effects of warfarin.
L-carnitine, the parent compound of propionyl-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 propionyl-L-carnitine and warfarin.
Brand information
Manufacturer and brand details for Optimized Carnitine, from the product label.
Life Extension
See all Life Extension products- Name
- Quality Supplements and Vitamins, Inc.
- City
- Ft. Lauderdale
- State
- FL
- ZipCode
- 33309
- Phone Number
- 1-866-280-2852
- Web Address
- LifeExtension.com
Optimized Carnitine by Life Extension: Common Questions
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The Full Monographs Behind Optimized Carnitine’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Acetyl-l-carnitine
Interacts with 203 drugsAcetyl-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 → Herb & supplement monographPropionyl-l-carnitine
Interacts with 19 drugsPropionyl-l-carnitine is a form of the amino acid derivative carnitine that the body uses to help turn fat into energy, and it is studied mostly for circulation problems like peripheral arte...
Read the full Propionyl-l-carnitine monograph →Sources & How We Checked
Optimized Carnitine'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 34 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
- 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
- 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
- Spagnoli A, Lucca U, Menasce G, et al. Long-term acetyl-L-carnitine treatment in Alzheimer's Disease. Neurology 1991;41:1726-32. PubMed
- 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
- 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
- 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
- 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
- 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
- Martinez E, Domingo P, Roca-Cusachs A. Potentiation of acenocoumarol action by L-carnitine. J Intern Med 1993;233:94.
- Hudson S, Tabet N. Acetyl-L-carnitine for dementia. Cochrane Database Syst Rev 2003;2:CD003158.. PubMed
- Bachmann HU, Hoffmann A. Interaction of food supplement L-carnitine with oral anticoagulant acenocoumarol. Swiss Med Wkly 2004;134:385. PubMed
- 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
- 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
- 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.
- 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.
- 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.
- 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
- 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
- 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
- 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.
- 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
- 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
Propionyl-l-carnitine 12 references
- Cherchi A, Lai C, Onnis E, et al. Propionyl carnitine in stable effort angina. Cardiovasc Drugs Ther 1990;4:481-6. PubMed
- Bartels GL, Remme WJ, den Hartog FR, et al. Additional anti-ischemic effects of long-term L-propionylcarnitine in anginal patients treated with conventional antianginal therapy. Cardiovasc Drugs Ther 1995;9:749-53.
- Caponnetto S, Canale C, Masperone MA, et al. Efficacy of L-propionylcarnitine treatment in patients with left ventricular dysfunction. Eur Heart J 1994;15:1267-73. PubMed
- 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
- Martinez E, Domingo P, Roca-Cusachs A. Potentiation of acenocoumarol action by L-carnitine. J Intern Med 1993;233:94.
- Bachmann HU, Hoffmann A. Interaction of food supplement L-carnitine with oral anticoagulant acenocoumarol. Swiss Med Wkly 2004;134:385. PubMed
- Gentile V, Vicini P, Prigiotti G, et al. Preliminary observations on the use of propionyl-L-carnitine in combination with sildenafil in patients with erectile dysfunction and diabetes. Curr Med Res Opin 2004;20:1377-84. PubMed
- 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
- Brass EP, Koster D, Hiatt WR, Amato A. A systematic review and meta-analysis of propionyl-L-carnitine effects on exercise performance in patients with claudication. Vasc Med 2013;18:3-12.
- Hiatt WR, Creager MA, Amato A, Brass EP. Effect of propionyl-L-carnitine on a background of monitored exercise in patients with claudication secondary to peripheral artery disease. J Cardiopulm Rehabil Prev 2011;31:125-32. PubMed
- Jacobs PL, Goldstein ER, Blackburn W, et al. Glycine propionyl-L-carnitine produces enhanced anaerobic work capacity with reduced lactate accumulation in resistance trained males. J Int Soc Sports Nutr 2009;6:9. PubMed
- Jacobs PL, Goldstein ER. Long-term glycine propionyl-l-carnitine supplementation and paradoxical effects on repeated anaerobic sprint performance. J Int Soc Sports Nutr 2010;7:35.
See these in context on the Propionyl-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