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Acetyl-L-Carnitine (ALCAR)Evidence & Dosage

Mitochondria, neuroprotection, and energy metabolism.

Studies last updated

Evidence at a glance

Total studies
1,000
With abstract
50
Meta / Systematic / RCT
154
Highly cited
50
Publication years
1966–2026

Acetyl-L-Carnitine (ALCAR) in the context of Cognition

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Top studies on Acetyl-L-Carnitine (ALCAR)

Ranked by influential-citation count and publication year.

  1. An integrated meta-analysis of peripheral blood metabolites and biological functions in major depressive disorder.

    Mol Psychiatry2021n=49Meta-Analysis133 influential citations

    Major depressive disorder (MDD) is a serious mental illness, characterized by high morbidity, which has increased in recent decades. However, the molecular mechanisms underlying MDD remain unclear. Previous studies have identified altered…

    Finding: The meta-analysis identified 23 metabolites that differed significantly between MDD patients and controls across 46 studies.

  2. Nicotinamide riboside supplementation alters body composition and skeletal muscle acetylcarnitine concentrations in healthy obese humans.

    Am J Clin Nutr2020n=15RCT69 influential citations

    <h4>Background</h4>Nicotinamide riboside (NR) is an NAD+ precursor that boosts cellular NAD+ concentrations. Preclinical studies have shown profound metabolic health effects after NR supplementation.<h4>Objectives</h4>We aimed to…

  3. Effect of metabolic and antioxidant supplementation on sperm parameters in oligo-astheno-teratozoospermia, with and without varicocele: A double-blind placebo-controlled study.

    Andrologia2018n=104RCT69 influential citations

    Since sperm require high energy levels to perform their specialised function, it is vital that essential nutrients are available for spermatozoa when they develop, capacitate and acquire motility. However, they are vulnerable to a lack of…

  4. Long-term acetyl-L-carnitine treatment in Alzheimer's disease.

    Neurology1991n=130RCT62 influential citations

    In a double-blind, placebo-controlled, parallel-group, randomized clinical trial, we studied the efficacy of long-term (1-year) oral treatment with acetyl-L-carnitine in 130 patients with a clinical diagnosis of Alzheimer's disease. We…

  5. Double-blind, randomised, placebo-controlled trial on the effect of L-carnitine and L-acetylcarnitine on sperm parameters in men with idiopathic oligoasthenozoospermia.

    Andrologia2019n=175RCT62 influential citations

    Carnitine is essential for energy metabolism and spermatozoa maturation. Combining L-carnitine and L-acetylcarnitine with micronutrients has been investigated as a treatment for infertility in men. We evaluated the effects of a therapeutic…

  6. A placebo-controlled double-blind randomized trial of the use of combined l-carnitine and l-acetyl-carnitine treatment in men with asthenozoospermia.

    Fertil Steril2004n=60RCT60 influential citations

    <h4>Objective</h4>To determine the efficacy of combined l-carnitine and l-acetyl-carnitine therapy in infertile males with oligo-astheno-teratozoospermia.<h4>Design</h4>Placebo-controlled double-blind randomized…

  7. Acetyl-l-carnitine deficiency in patients with major depressive disorder.

    Proc Natl Acad Sci U S A2018Clinical Trial54 influential citations

    Significance Identifying biological targets in major depressive disorder (MDD) is a critical step for development of effective mechanism-based medications. The epigenetic agent acetyl- l -carnitine (LAC) has rapid and enduring…

  8. Randomized double-blind placebo-controlled trial of acetyl-L-carnitine for the prevention of taxane-induced neuropathy in women undergoing adjuvant breast cancer therapy.

    J Clin Oncol2013n=409RCT52 influential citations

    <h4>Purpose</h4>Chemotherapy-induced peripheral neuropathy (CIPN) is common and leads to suboptimal treatment. Acetyl-L-carnitine (ALC) is a natural compound involved in neuronal protection. Studies have suggested ALC may be effective for…

  9. 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 Care2005n=125RCT50 influential citations

    <h4>Objective</h4>We evaluated frozen databases from two 52-week randomized placebo-controlled clinical diabetic neuropathy trials testing two doses of acetyl-L-carnitine (ALC): 500 and 1,000 mg/day t.i.d.<h4>Research design and…

  10. Neuropsychiatric Manifestations of COVID-19 Disease and Post COVID Syndrome: The Role of N-acetylcysteine and Acetyl-L-carnitine.

    Curr Neuropharmacol2025n=19review50 influential citations

    COVID-19 is associated with neuropsychiatric symptoms, such as anosmia, anxiety, depression, stress-related reactions, and psychoses. The illness can cause persistent cognitive impairment and "brain fog", suggesting chronic brain…

Frequently asked

What does the evidence say about Acetyl-L-Carnitine (ALCAR)?
The meta-analysis identified 23 metabolites that differed significantly between MDD patients and controls across 46 studies.
What dosage was studied?
• Peripheral blood metabolite profiling in MDD (meta-analysis of observed studies; no intervention) (not reported) • Nicotinamide riboside supplementation (1000 mg/d) • Supplementation with l-carnitine, acetyl-l-carnitine, and other micronutrients (Not reported)
Are there safety considerations for Acetyl-L-Carnitine (ALCAR)?
• not reported • No adverse events or side effects were reported at 1000 mg/d. • NR was described as well tolerated during 6 weeks. • No adverse events were reported in the excerpt.

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