Product Image

Ciltep

NS Natural Stacks
4.6
★ ★ ★ ★ ★
(514 ratings)
Acetyl L-Carnitine 750 mg
Phenylalanine 500 mg
Product Image
Score77
ALCAR and phenylalanine provide credible cognitive-energy support. Higher cost and important phenylalanine and forskolin precautions narrow its fit.
How scoring works
Quantity:60 Capsule(s) • (20 servings)
Goals:
Productivity Boost
Mental Focus
Metabolism Boost
Energy
Anti-Aging
Cognitive Support
Brain Health
Weight Loss

Score 77

ALCAR and phenylalanine provide credible cognitive-energy support. Higher cost and important phenylalanine and forskolin precautions narrow its fit.
How scoring works
$23.95($1.19 per serving)
Walmart
$ 23.95
Report prices

Analysis

Acetyl-L-carnitine at 750 mg supports cellular and brain energy, while 500 mg L-phenylalanine supplies a catecholamine precursor. P5P provides a relevant cofactor for amino-acid metabolism.

Artichoke and forskolin add a signaling strategy, but evidence for that pairing is less established than for the core nutrients. The formula is better aligned with focus and productivity than direct weight loss.

All actives are disclosed at purposeful amounts in three capsules. Only 20 servings and a relatively high serving cost weaken practical value.

Who is it for
  • Adults seeking stimulant-free cognitive energy
  • People wanting ALCAR with phenylalanine
  • Users comfortable with a three-capsule serving
Best for
  • Mental focus
  • Productivity support
  • Brain-energy supplementation

Pros

  • Provides 750 mg ALCAR
  • Includes 500 mg L-phenylalanine
  • Uses active P5P vitamin B6
  • Discloses standardized botanical markers

Cons

  • High serving cost
  • Only 20 servings
  • ALCAR purity details are absent
  • Weight-loss evidence for the full stack is limited

Warnings

  • People with phenylketonuria must not use phenylalanine
  • Phenylalanine can interact with MAO inhibitors and may affect blood pressure
  • Forskolin may lower blood pressure
  • Forskolin may add to bleeding risk with anticoagulant or antiplatelet medicines

Nutrient quality

85 Highest impact

Pyridoxal phosphate, standardized artichoke, and named acetyl-L-carnitine support form quality. Artichoke, acetyl-L-carnitine, and phenylalanine are meaningful, while forskolin is a smaller supporting amount.

.

Ingredient transparency

81 Highest impact

Active amounts are stated and no proprietary blend hides a core dose. Missing excipient details and complete use directions leave the supplied label information incomplete.

.

Customer satisfaction

65 Moderate impact

The supplied aggregate satisfaction average provides a broad signal, while the response volume determines how stable it appears. No comment-level evidence is available to assess repeated complaints or confirm intended-use experiences.

.

Value for money

71 High impact

The formula offers mixed but reasonable serving value. The formula is focused and its supporting ingredients have plausible nootropic roles.

.
Report analysis

Goals

Productivity Boost
Productivity Boost
Impact
Highest effect
B+ Goal FitB+ Strength of SupportA- CoverageA- Formula Quality
Acetyl L-Carnitine · 750 mgAcetyl L-Carnitine · 750 mg

Acetyl-L-carnitine and phenylalanine support cognitive energy and neurotransmitter synthesis, while the botanical components target signaling and mental stamina. The stack has strong mechanistic breadth, though clinical evidence for the complete combination is limited.

Most actives are disclosed at meaningful amounts and vitamin B6 uses its active coenzyme form. L-phenylalanine makes the product unsuitable for people with phenylketonuria.

Study evidence
Acetyl L-Carnitine Supportive 1 study
Acetyl L-Carnitine Supportive 1 study
Mental Focus
Mental Focus
Impact
Highest effect
B Goal FitA Strength of SupportB CoverageA- Formula Quality
Acetyl L-Carnitine · 750 mg

Acetyl-L-carnitine and phenylalanine support mental energy and neurotransmitter building blocks, while active B6 assists amino-acid metabolism. Artichoke and forskolin follow a cyclic-AMP strategy, but direct human focus evidence for that pairing is limited.

The main cognitive actives are supplied at meaningful amounts and fully disclosed. Forskolin may lower blood pressure, so the formula warrants care for users taking blood-pressure medicines or prone to low blood pressure.

Study evidence
Acetyl L-Carnitine Supportive 7 studies
Phenylalanine No effect 7 studies
Metabolism Boost
Metabolism Boost
Impact
Highest effect
B+ Goal FitB+ Strength of SupportB+ CoverageB Formula Quality
Acetyl L-Carnitine · 750 mg

Acetyl-L-carnitine directly supports fatty-acid transport into mitochondria at a meaningful amount. The added botanicals broaden the formula, but evidence for their metabolic effects is less consistent.

Pyridoxal phosphate and disclosed extract amounts make the combination reasonably transparent. L-phenylalanine makes the formula unsuitable for people with phenylketonuria.

Study evidence
Acetyl L-Carnitine Adverse 1 study
Energy
Energy
Impact
High effect
B- Goal FitA- Strength of SupportB- CoverageA Formula Quality
Acetyl L-Carnitine · 750 mg

Acetyl-L-carnitine, phenylalanine, active vitamin B6, and standardized botanicals target mental energy and neurotransmitter signaling. Several core actives have meaningful disclosed amounts.

The blend is more nootropic than broadly energizing, and forskolin can lower blood pressure or interact with blood-pressure medicines. Evidence for the full combination is limited despite reasonable transparency.

Study evidence
Acetyl L-Carnitine Supportive 19 studies
Anti-Aging
Anti-Aging
Impact
High effect
B Goal FitB+ Strength of SupportB+ CoverageB+ Formula Quality

Acetyl-L-carnitine provides meaningful mitochondrial and cognitive support, while phenylalanine and active vitamin B6 support neurotransmitter production. Artichoke and forskolin add metabolic and signaling breadth.

The formula has plausible multi-pathway logic, but evidence for the complete combination on age-related outcomes is limited. L-phenylalanine makes the product unsuitable for people with phenylketonuria because they cannot safely metabolize phenylalanine.

Study evidence
Acetyl L-Carnitine Supportive 1 study
Cognitive Support
Cognitive Support
Impact
High effect
B Goal FitA- Strength of SupportB+ CoverageB- Formula Quality
Acetyl L-Carnitine · 750 mg

Acetyl-L-carnitine and phenylalanine target brain energy and neurotransmitter production, giving the stack clear cognitive relevance. Acetyl-L-carnitine has useful human evidence, while the artichoke and forskolin signaling concept is less clinically established for cognition.

Acetyl-L-carnitine at 750 mg and phenylalanine at 500 mg are meaningful, with disclosed supporting amounts. P5P and standardized marker amounts improve disclosure, though acetyl-L-carnitine purity details are absent. L-phenylalanine makes the product unsuitable for people with phenylketonuria.

Study evidence
Acetyl L-Carnitine Supportive 20 studies

Ingredients

IngredientAmount per serving
Artichoke extract (Total Caffeoylquinic Acids)
 900 mg
Coleus forskohlii (root) extract (Forskolin)
 20 mg
L-Phenylalanine
500 mg
Acetyl-L-Carnitine
750 mg
Gluten Free Adults 18–50
Report overview
Acetyl L-Carnitine · 750 mg OverallScore84
B Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyC Value

The 750 mg ALCAR dose is clearly disclosed and fits the usual effective range. Its unspecified salt and lack of stated purity or manufacturing evidence reduce confidence in ingredient sourcing. Added artichoke extract and L-phenylalanine broaden the formula, but L-phenylalanine makes it unsuitable for people with phenylketonuria.

View ingredientView products
Phenylalanine · 500 mg OverallScore82
A+ Active Ingredient Quality & BioavailabilityA- Dose, Safety & Label TransparencyD- Value

The targeted nootropic stack supplies 500 mg of clearly identified L-phenylalanine alongside P5P, forskolin, and acetyl-L-carnitine. Its formula avoids the heavy amino-acid competition found in complete proteins, although the active amount is comparatively costly. The supplied information does not show a phenylketonuria warning, so people with PKU should not use it.

View ingredientView products
Loading alternative details
73 Performance

Vital Brain Powder

Vital Nutrients
<p>Acetyl-L-carnitine, glycerophosphocholine, and phosphatidylserine provide more direct cognitive membrane and neurotransmitter support than the original's artichoke and forskolin components. The carnitine amount is also slightly higher, but the serving cost is high and phenylalanine is absent.</p>
81 Performance

CoQ10 + Alpha Lipoic Acid + Acetyl L-Carnitine HCl

Nature's Lab
<p>Acetyl-L-carnitine, CoQ10, and alpha-lipoic acid create a more focused mitochondrial and antioxidant combination than the original. The formula omits phenylalanine and the artichoke-forskolin pair, while alpha-lipoic acid may compound glucose-lowering medicines.</p>
82 Performance

Optimized Carnitine

Life Extension
<p>Three specific carnitine forms provide broader mitochondrial and circulation support at a higher total carnitine amount than the original. The dose is aggressive for routine use, and the formula does not retain phenylalanine, artichoke, forskolin, or vitamin B6.</p>
87 Budget

Acetyl L-Carnitine 500 mg

Swanson
<p>A much lower serving cost retains acetyl-L-carnitine hydrochloride in a simple, clearly dosed formula. The amount is lower than the original and it omits phenylalanine, artichoke, forskolin, and vitamin B6, so it suits focused carnitine use rather than a complete nootropic stack.</p>
87 Budget

L-Phenylalanine 500 mg

NOW
<p>A much lower serving cost matches the original's phenylalanine amount without unrelated additions. It leaves out acetyl-L-carnitine and the other nootropic ingredients, and people with phenylketonuria should avoid supplemental phenylalanine.</p>
86 Budget

Acetyl L-Carnitine 500 mg

Source Naturals
<p>A substantially lower serving cost provides a clear acetyl-L-carnitine hydrochloride dose for energy and cognitive support. The focused design is easier to assess than the original blend, but it supplies less carnitine and omits phenylalanine, artichoke, forskolin, and vitamin B6.</p>
84 Value

Acetyl L-Carnitine & Alpha-Lipoic Acid

Source Naturals
<p>A lower serving cost combines acetyl-L-carnitine with a meaningful alpha-lipoic acid amount, improving mitochondrial and antioxidant breadth. It provides less carnitine than the original and omits phenylalanine, artichoke, forskolin, and active vitamin B6; alpha-lipoic acid may also lower blood sugar alongside medicines.</p>
84 Value

Acetyl-L-Carnitine Arginate

Life Extension
<p>Two clearly identified acetyl-L-carnitine salts provide a substantial focused serving at much better recurring value than the original. The total carnitine amount is somewhat lower, and the simpler design does not include phenylalanine or the original botanical pathways.</p>
86 Value

Acetyl-L-Carnitine 500 mg

The Vitamin Shoppe
<p>A much lower serving cost preserves a clearly identified acetyl-L-carnitine hydrochloride dose without extra ingredients. It is a better-value choice for focused carnitine use, though the amount is lower and the original's phenylalanine, botanicals, and active vitamin B6 are absent.</p>
Report alternatives

Sources

Published studies used for the product analysis and the top-ranked studies for each ingredient and goal.

  1. Acetyl-L-carnitine improves cognitive functions in severe hepatic encephalopathy: a randomized and controlled clinical trial.
    Malaguarnera M; Vacante M; Motta M; Giordano M; Malaguarnera G; Bella R; Nunnari G; Rampello L; Pennisi G · Metabolic brain disease · 2012
    Randomized trial61 participantsBrain Health Cognitive Support forAcetyl L-Carnitine
  2. Oral acetyl-L-carnitine therapy reduces fatigue in overt hepatic encephalopathy: a randomized, double-blind, placebo-controlled study.
    Malaguarnera M; Vacante M; Giordano M; Pennisi G; Bella R; Rampello L; Malaguarnera M; Li Volti G; Galvano F · The American journal of clinical nutrition · 2011
    Randomized trial121 participantsEnergy forAcetyl L-Carnitine
  3. Double-blind, placebo controlled study of acetyl-l-carnitine in patients with Alzheimer's dementia.
    Rai G; Wright G; Scott L; Beston B; Rest J; Exton-Smith AN · Current medical research and opinion · 1990
    Randomized trial36 participantsBrain Health forAcetyl L-Carnitine
  4. Carnitine for fatigue in multiple sclerosis.
    Tejani AM; Wasdell M; Spiwak R; Rowell G; Nathwani S · The Cochrane database of systematic reviews · 2012
    Systematic review1 studies pooledEnergy forAcetyl L-Carnitine
  5. Mental impairment in aging: selection of patients, methods of evaluation and therapeutic possibilities of acetyl-L-carnitine.
    Passeri M; Iannuccelli M; Ciotti G; Bonati PA; Nolfe G; Cucinotta D · International journal of clinical pharmacology research · 1989
    Randomized trial30 participantsBrain Health forAcetyl L-Carnitine
  6. Double-blind, multicenter trial comparing acetyl l-carnitine with placebo in the treatment of fibromyalgia patients.
    Rossini M; Di Munno O; Valentini G; Bianchi G; Biasi G; Cacace E; Malesci D; La Montagna G; Viapiana O; Adami S · Clinical and experimental rheumatology · 2007
    Randomized trial102 participantsEnergy forAcetyl L-Carnitine
  7. The Effect of Acylcarnitines on Cognitive Function: A Two-Sample Mendelian Randomization Study.
    Luan S; Zhang J; Wang C; Wang Z; Zhou J · Brain and behavior · 2025
    OtherBrain Health forAcetyl L-Carnitine
  8. Acylcarnitines metabolism in depression: association with diagnostic status, depression severity and symptom profile in the NESDA cohort.
    Montanari S; Jansen R; Schranner D; Kastenmüller G; Arnold M; Janiri D; Sani G; Bhattacharyya S; Mahmoudian Dehkordi S; Dunlop BW; Rush AJ; Penninx BWHJ; Kaddurah-Daouk R; Milaneschi Y · Translational psychiatry · 2025
    Cohort study2,574 participantsEnergy forAcetyl L-Carnitine
  9. Acetyl-L-carnitine Slows the Progression from Prefrailty to Frailty in Older Subjects: A Randomized Interventional Clinical Trial.
    Malaguarnera G; Catania VE; Bertino G; Chisari LM; Castorina M; Bonfiglio C; Cauli O; Malaguarnera M · Current pharmaceutical design · 2022
    Randomized trial92 participantsAnti-Aging forAcetyl L-Carnitine
  10. Acetyl-L-carnitine treatment in minimal hepatic encephalopathy.
    Malaguarnera M; Gargante MP; Cristaldi E; Vacante M; Risino C; Cammalleri L; Pennisi G; Rampello L · Digestive diseases and sciences · 2008
    Randomized trial125 participantsBrain Health Cognitive Support forAcetyl L-Carnitine
  11. Long-term acetyl-L-carnitine treatment in Alzheimer's disease.
    Spagnoli A; Lucca U; Menasce G; Bandera L; Cizza G; Forloni G; Tettamanti M; Frattura L; Tiraboschi P; Comelli M · Neurology · 1991
    Randomized trial130 participantsBrain Health Cognitive Support forAcetyl L-Carnitine
  12. Pharmaco-electroencephalographic and clinical effects of the cholinergic substance--acetyl-L-carnitine--in patients with organic brain syndrome.
    Herrmann WM; Dietrich B; Hiersemenzel R · International journal of clinical pharmacology research · 1990
    Randomized trialBrain Health forAcetyl L-Carnitine
  13. Acetyl-L-carnitine in the treatment of mildly demented elderly patients.
    Passeri M; Cucinotta D; Bonati PA; Iannuccelli M; Parnetti L; Senin U · International journal of clinical pharmacology research · 1990
    Randomized trial60 participantsBrain Health Mental Focus forAcetyl L-Carnitine
  14. The Association between Dietary Amino Acid Intake and Cognitive Decline 8 Years Later in Japanese Community-Dwelling Older Adults.
    Kinoshita K; Otsuka R; Takada M; Tsukamoto-Yasui M; Nishita Y; Tange C; Tomida M; Shimokata H; Kuzuya M; Imaizumi A; Arai H · The journal of nutrition, health & aging · 2021
    Cohort study427 participantsBrain Health forPhenylalanine
  15. Magnetic resonance imaging in phenylketonuria: reversal of cerebral white matter change.
    Cleary MA; Walter JH; Wraith JE; White F; Tyler K; Jenkins JP · The Journal of pediatrics · 1995
    Non-randomized trial41 participantsBrain Health forPhenylalanine
  16. [Cross-sectional association between the amino acid intake and episodic memory in middle- and old-aged community dwellers].
    Kinoshita K; Otsuka R; Takada M; Tsukamoto-Yasui M; Nishita Y; Tange C; Tomida M; Shimokata H; Imaizumi A; Arai H · Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics · 2021
    Cross-sectional study2,082 participantsBrain Health forPhenylalanine
  17. Improved dietary control results in improvements in indices of white matter structure in adults with phenylketonuria: the ReDAPT study.
    Kang MJY; Adamson C; Malpas CB; Winton-Brown T; Burgess N; Fazio T; Velakoulis D; Desmond P; Venkatraman V; De Jong G; Walterfang M · Acta neuropsychiatrica · 2026
    Single-arm trial7 participantsBrain Health forPhenylalanine
  18. [Brain white matter lesions of children with phenylketonuria before and after treatment].
    Wang ZX; Zhou ZS; Yu WM · Zhongguo dang dai er ke za zhi = Chinese journal of contemporary pediatrics · 2006
    Single-arm trial19 participantsBrain Health forPhenylalanine
  19. A double-blind, parallel, multicenter comparison of L-acetylcarnitine with placebo on the attention deficit hyperactivity disorder in fragile X syndrome boys.
    Torrioli MG; Vernacotola S; Peruzzi L; Tabolacci E; Mila M; Militerni R; Musumeci S; Ramos FJ; Frontera M; Sorge G; Marzullo E; Romeo G; Vallee L; Veneselli E; Cocchi E; Garbarino E; Moscato U; Chiurazzi P; D'Iddio S; Calvani M; Neri G · American journal of medical genetics. Part A · 2008
    Randomized trial63 participantsCognitive Support forAcetyl L-Carnitine
  20. Acetyl L-carnitine (ALC) treatment in elderly patients with fatigue.
    Malaguarnera M; Gargante MP; Cristaldi E; Colonna V; Messano M; Koverech A; Neri S; Vacante M; Cammalleri L; Motta M · Archives of gerontology and geriatrics · 2008
    Randomized trial96 participantsCognitive Support forAcetyl L-Carnitine
  21. The supplementation of acetyl-L-carnitine decreases fatigue and increases quality of life in patients with hepatitis C treated with pegylated interferon-α 2b plus ribavirin.
    Malaguarnera M; Vacante M; Bertino G; Neri S; Malaguarnera M; Gargante MP; Motta M; Lupo L; Chisari G; Bruno CM; Pennisi G; Bella R · Journal of interferon & cytokine research : the official journal of the International Society for Interferon and Cytokine Research · 2012
    Randomized trial60 participantsEnergy forAcetyl L-Carnitine
  22. Acetyl-L-carnitine reduces depression and improves quality of life in patients with minimal hepatic encephalopathy.
    Malaguarnera M; Bella R; Vacante M; Giordano M; Malaguarnera G; Gargante MP; Motta M; Mistretta A; Rampello L; Pennisi G · Scandinavian journal of gastroenterology · 2011
    Randomized trial67 participantsEnergy forAcetyl L-Carnitine
  23. A prospective study to evaluate the efficacy and safety of oral acetyl-L-carnitine for the treatment of chemotherapy-induced peripheral neuropathy.
    Sun Y; Shu Y; Liu B; Liu P; Wu C; Zheng R; Zhang X; Zhuang Z; Deng Y; Zheng L; Xu Q; Jiang B; Ouyang X; Gao J; Xu N; Li X; Jiang S; Liang C; Yao Y · Experimental and therapeutic medicine · 2020
    Randomized trial239 participantsEnergy forAcetyl L-Carnitine
  24. Metabolomic biomarkers for (R, S)-ketamine and (S)-ketamine in treatment-resistant depression and healthy controls: A systematic review.
    Kumar R; Nuñez NA; Joshi N; Joseph B; Verde A; Seshadri A; Cuellar Barboza AB; Prokop LJ; Medeiros GC; Singh B · Bipolar disorders · 2024
    Systematic reviewEnergy forAcetyl L-Carnitine
  25. Acetyl-L-Carnitine Supplementation During HCV Therapy With Pegylated Interferon-α 2b Plus Ribavirin: Effect on Work Performance; A Randomized Clinical Trial.
    Malaguarnera G; Pennisi M; Gagliano C; Vacante M; Malaguarnera M; Salomone S; Drago F; Bertino G; Caraci F; Nunnari G; Malaguarnera M · Hepatitis monthly · 2014
    Randomized trial62 participantsMental Focus Productivity Boost forAcetyl L-Carnitine
  26. [Psycho-functional changes in attention and learning under the action of L-acetylcarnitine in 17 young subjects. A pilot study of its use in mental deterioration].
    Lino A; Boccia MM; Rusconi AC; Bellomonte L; Cocuroccia B · La Clinica terapeutica · 1992
    Non-randomized trial17 participantsMental Focus forAcetyl L-Carnitine
  27. Acetyl-L-carnitine (ALC) in attention-deficit/hyperactivity disorder: a multi-site, placebo-controlled pilot trial.
    Arnold LE; Amato A; Bozzolo H; Hollway J; Cook A; Ramadan Y; Crowl L; Zhang D; Thompson S; Testa G; Kliewer V; Wigal T; McBurnett K; Manos M · Journal of child and adolescent psychopharmacology · 2008
    Randomized trial112 participantsMental Focus forAcetyl L-Carnitine
  28. Acetyl-L-carnitine for patients with hepatic encephalopathy.
    Martí-Carvajal AJ; Gluud C; Arevalo-Rodriguez I; Martí-Amarista CE · The Cochrane database of systematic reviews · 2019
    Meta-analysis398 participants5 studies pooledMental Focus forAcetyl L-Carnitine
  29. Cognition after a 4-week high phenylalanine intake in adults with phenylketonuria - a randomized controlled trial.
    Trepp R; Muri R; Maissen-Abgottspon S; Haynes AG; Hochuli M; Everts R · The American journal of clinical nutrition · 2024
    Randomized trial30 participantsMental Focus forPhenylalanine
  30. A systematic review of cognitive functioning in early treated adults with phenylketonuria.
    Hofman DL; Champ CL; Lawton CL; Henderson M; Dye L · Orphanet journal of rare diseases · 2019
    Systematic review16 studies pooledMental Focus forPhenylalanine
  31. Are Functional Brain Networks Sensitive to High Phenylalanine in Adults With Phenylketonuria?
    Vallesi V; Morishima Y; Winiger L; Trepp R; Everts R; Muri R · JIMD reports · 2026
    Randomized trial23 participantsMental Focus forPhenylalanine
  32. Sustained attention in untreated non-PKU-hyperphenylalaninemia.
    Weglage J; Schmidt E; Fünders B; Pietsch M; Ullrich K · Journal of clinical and experimental neuropsychology · 1997
    Case-control study48 participantsMental Focus forPhenylalanine
  33. Effects of L-histidine depletion and L-tyrosine/L-phenylalanine depletion on sensory and motor processes in healthy volunteers.
    van Ruitenbeek P; Sambeth A; Vermeeren A; Young SN; Riedel WJ · British journal of pharmacology · 2009
    Clinical trial17 participantsMental Focus forPhenylalanine
  34. Low Bioavailability and High TMAO Production: Novel Insights Into Acetylcarnitine and Carnitine Metabolism.
    Krims-Davis K; Ozola M; Razzivina V; Gukalova B; Konrade I; Dambrova M; Liepinsh E · Molecular nutrition & food research · 2025
    Randomized trialMetabolism Boost forAcetyl L-Carnitine