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📰Read the full Alpha-Lipoic Acid evidence review on GMJ News →Complete clinical article, references and updates on news.gmj.ge. This page is the structured safety summary.⚠ Diabetic patient starting ALA on insulin or sulfonylurea — monitor for hypoglycemia [3]
⚠ Patient on levothyroxine starting ALA — may alter T3/T4 levels; check thyroid function at 6 weeks [2]
⚠ Patient on chemotherapy — ALA chelates platinum and may reduce efficacy; discuss with oncologist [2]
⚠ Take on EMPTY stomach — food reduces bioavailability by 40% [2]
ℹ️ Not obtained from food. Made by the body and present in trace amounts in food; there is no established daily dietary target.
🔬 Lab interpreter
Recommended test
Fasting blood glucose / HbA1c
Fasting blood glucose / HbA1c
Reference range / target
Per diabetes guidelines
Per diabetes guidelines
Primary concern is hypoglycemia from ALA's glucose-lowering effect combined with diabetes medications [3].
Full lab monitoring ↓⚕ For professionals — confirm ranges against your local laboratory.
Clinical verdict
ALA is a unique dual-soluble antioxidant and the only supplement that is also a prescription drug for diabetic neuropathy in Germany. 600 mg/day orally is the standard therapeutic dose (ALADIN/NATHAN trials). Take on an empty stomach. Monitor glucose in diabetic patients — ALA enhances insulin sensitivity. R-ALA is the active enantiomer but racemic ALA is well-studied [2] [3] [4].
1 How much do I need?
👤 Adults: Specific dosage data under clinical review
👴 Elderly: Specific dosage data under clinical review
🤰 Pregnancy: See guidance
No established dose. Limited safety data. Avoid unless directed by physician. Glucose-lowering effect is a theoretical concern [2].
👦 Pediatric: See guidance
No established dose. ALA is not routinely used in pediatric populations. Rare use for genetic mitochondrial disorders under specialist supervision [2].
🏃 Athletes: Standard dose
⚖️ Obesity: Standard dose
Fat-soluble compounds may require dose adjustment in obesity.
🩺 Renal: Consult specialist
Dose adjustment may be needed in renal impairment.
🌱 Vegan: Standard dose
How to take
🍽 Timing: Take 30 minutes BEFORE meals on an empty stomach. Food reduces bioavailability by ~40% [2].
💊 With food: AVOID food — take fasting [2].
2 Which form?
| Form | Bioavailability | Vegan | Cost |
|---|---|---|---|
| ['Racemic ALA (R/S-ALA)', 'common', '50:50 mixture of R- and S-enantiomers. Most supplements and clinical trials use racemic ALA. ~30% bioavailability [2].'] | Standard | Check label | |
| ['R-lipoic acid (R-ALA)', 'preferred', 'The naturally occurring enantiomer. The biologically active form as mitochondrial cofactor. Approximately 40–50% higher peak plasma levels than racemic ALA. Less stable (requires stabilization, e.g., sodium R-lipoate) [2].'] | Standard | Check label | |
| ['IV alpha-lipoic acid', '', 'Used in clinical trials for diabetic neuropathy (600 mg/day IV, ALADIN trial protocol). Faster onset than oral. Prescription-only in most jurisdictions [3].'] | Standard | Check label |
3 Common questions
Is R-ALA better than racemic ALA? ▼
R-ALA is the naturally occurring, biologically active form and achieves 40–50% higher plasma levels than racemic ALA [2]. However, most clinical trials (ALADIN, NATHAN) used racemic ALA. R-ALA may offer advantages but is more expensive and less stable. Both forms are effective.
Does ALA help with diabetic neuropathy? ▼
Can ALA cause low blood sugar? ▼
ALA enhances insulin sensitivity and can lower blood glucose. In patients on insulin or sulfonylureas, this may cause hypoglycemia [3]. Glucose monitoring is advisable when starting ALA in diabetic patients.
Should I take ALA with food? ▼
No — take on an empty stomach (30 minutes before meals). Food reduces bioavailability by approximately 40% [2].
4 Clinical evidence
Strong
Diabetic peripheral neuropathy (IV): the ALADIN trial (n = 328) demonstrated significant improvement in neuropathy symptoms with IV ALA 600 mg/day over 3 weeks [3]. Essential cofactor for pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase in mitochondrial energy metabolism [1]. HIGH
Moderate
Diabetic peripheral neuropathy (oral): the NATHAN II trial (n = 460) showed improvement in neuropathic impairment score with oral ALA 600 mg/day over 4 years [4]. Weight loss: meta-analysis of 12 RCTs showed modest weight loss (~1.3 kg) with ALA supplementation [5]. Oxidative stress reduction: well-demonstrated in multiple trials [2]. Blood glucose reduction: modest fasting glucose lowering in diabetic patients [3]. MODERATE
Insufficient
Alzheimer disease: preclinical and small pilot data only [2]. Multiple sclerosis: small pilot studies, Phase II trials underway [2]. Liver disease (NAFLD): some positive data but insufficient for recommendation [2]. Cancer prevention: preclinical only [2]. Anti-aging: theoretical based on mitochondrial mechanisms but not clinically proven [2]. LOW
5 Safety, toxicity & adverse events
Relative
⚠ Concurrent insulin/sulfonylureas — ALA enhances glucose uptake; monitor for hypoglycemia
⚠ Thiamine deficiency — ALA requires thiamine as cofactor; deficiency may worsen
⚠ Thyroid disorders — high-dose ALA may lower T3 levels
⚠ Concurrent cisplatin — ALA may reduce cisplatin efficacy (antioxidant protection of tumor cells)
🚩 Red flags
● Diabetic patient on insulin + ALA with hypoglycemic episodes — reduce insulin and ALA dose or adjust timing [3]
● Patient on levothyroxine with new thyroid symptoms after starting ALA — check TSH and free T4 [2]
● Cancer patient self-supplementing ALA during platinum chemotherapy — potential interference with efficacy [2]
6 Interactions
Drug interactions
Insulin and sulfonylureas Major
Mechanism: ALA enhances insulin sensitivity through AMPK activation and GLUT4 translocation. Additive glucose lowering with diabetes medications. [3]
Effect: Hypoglycemia, especially early in supplementation. [3]
Action: Monitor blood glucose closely for 2–4 weeks when starting ALA. May need to reduce insulin or sulfonylurea dose [3].
Levothyroxine Moderate
Mechanism: ALA may inhibit type I and type II deiodinases, reducing T4→T3 conversion. [2]
Effect: Altered thyroid hormone levels. May require thyroid dose adjustment. [2]
Action: Check TSH and free T4 at 6 weeks after starting ALA [2].
Cisplatin Moderate
Mechanism: ALA chelates divalent metal ions including platinum. May reduce cisplatin bioavailability and efficacy. May also reduce nephrotoxicity (protective effect). [2]
Effect: Uncertain net effect on chemotherapy efficacy. [2]
Action: Do not self-supplement during platinum chemotherapy without oncologist approval [2].
Supplement synergies
Coenzyme Q10 · 100–300 mg/day CoQ10
ALA regenerates reduced CoQ10 (ubiquinol) in the mitochondrial membrane. Complementary mitochondrial antioxidant support [1].
ALA regenerates reduced CoQ10 (ubiquinol) in the mitochondrial membrane. Complementary mitochondrial antioxidant support [1].
Vitamin C and E · Per individual RDA
ALA regenerates both oxidized vitamin C and vitamin E. Called the 'antioxidant of antioxidants' [1].
ALA regenerates both oxidized vitamin C and vitamin E. Called the 'antioxidant of antioxidants' [1].
Glutathione / NAC · 600–1,200 mg/day NAC
ALA increases intracellular glutathione by reducing oxidized glutathione (GSSG → 2GSH) and upregulating glutathione synthesis. NAC provides the cysteine substrate [1].
ALA increases intracellular glutathione by reducing oxidized glutathione (GSSG → 2GSH) and upregulating glutathione synthesis. NAC provides the cysteine substrate [1].
7 Regulatory
United States (FDA): Classified as a dietary supplement. No RDA (not an essential nutrient). Not FDA-approved as a drug for neuropathy [2].
European Union / Germany: Prescription drug for diabetic neuropathy in Germany (Thioctacid brand) since the 1960s. Also available as a supplement in some EU countries [3].
Japan (MHLW): Available as both dietary supplement and pharmaceutical product.
South Korea (MFDS): Available as dietary supplement ingredient. Also used in pharmaceutical formulations.
8 US supplement products
107
on-market products containing Alpha-Lipoic Acid (NIH DSLD)
Brands carrying Alpha-Lipoic Acid (46)
Click a brand to see its Alpha-Lipoic Acid products.
9 Frequently paired with
10 Cite this page
Vancouver: Pkhakadze G. Alpha-Lipoic Acid — safety profile [Internet]. Tbilisi: PHIG; 2026 [cited 2026 Sep 01]. Available from: https://supplement.ge/ingredients/alpha-lipoic-acid/
APA 7th: Pkhakadze, G. (2026). Alpha-Lipoic Acid — Safety profile. Public Health Institute of Georgia. https://supplement.ge/ingredients/alpha-lipoic-acid/
📋 Editorial information
Author: Prof. G. Pkhakadze, MD, MPH, PhD
Institution: Public Health Institute of Georgia (PHIG)
Affiliation: David Tvildiani Medical University (DTMU)
First published: January 2026
Last reviewed: 2026-05-29
Next review: March 2027
References: 7 cited sources
COI: SupplementIndex receives no funding from supplement manufacturers. All content independently authored by PHIG.
Process: Systematic literature review
📄 License & reuse
Published under Creative Commons Attribution 4.0 International (CC BY 4.0). You may share and adapt for any purpose with attribution.
Pkhakadze G. "Alpha-Lipoic Acid — Safety Profile." SupplementIndex, PHIG, 2026. https://supplement.ge/ingredients/alpha-lipoic-acid/ CC BY 4.0.
GP
Prof. G. Pkhakadze, MD, MPH, PhD
Professor of Public Health · Head of Department, DTMU
Editor-in-Chief, Georgian Medical Journal (ISSN 3088-4322)
Chair, Public Health Institute of Georgia · UEMS Public Health Section
Educational and public health purposes. CC BY 4.0. Consult your healthcare provider before starting any supplement. Corrections: info@accreditation.ge. Publisher: PHIG