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NAC (N-Acetyl Cysteine) Dosage Guide

Evidence:Strong
·

This content is for informational purposes only and does not constitute medical advice. Statements about dietary supplements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary — consult your healthcare provider before starting any supplement. Full disclaimer

General Dosage

600-1,200 mg daily in divided doses

Maximum dose: 2,400 mg/day is commonly used in psychiatric trials; higher doses used under medical supervision

Dosage Recommendations

General recommendation: 600-1,200 mg daily in divided doses

Timing: Take on an empty stomach for better absorption; can be divided into 2-3 doses

Dosage by Condition

Glutathione support
600-1,200 mg dailyStrong
Respiratory mucus thinning
600-1,200 mg dailyStrong
Psychiatric applications
1,200-2,400 mg dailyModerate
Liver support
600-1,200 mg dailyModerate

Upper limit: 2,400 mg/day is commonly used in psychiatric trials; higher doses used under medical supervision

Timing & Absorption

Take on an empty stomach for better absorption; can be divided into 2-3 doses

Can be taken with or without food.

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Full NAC (N-Acetyl Cysteine) Guide

References

  1. RCTGrant JE, Odlaug BL, Kim SW (2009). N-acetylcysteine, a glutamate modulator, in the treatment of trichotillomania: a double-blind, placebo-controlled study. Archives of General Psychiatry. DOI PubMed
  2. ReviewRushworth GF, Megson IL (2014). Existing and potential therapeutic uses for N-acetylcysteine: the need for conversion to intracellular glutathione for antioxidant benefits. Pharmacology & Therapeutics. DOI PubMed
  3. Meta-analysisViña I, Viña JR, Carranza M, Mariscal G (2025). Efficacy of N-Acetylcysteine in Polycystic Ovary Syndrome: Systematic Review and Meta-Analysis.. Nutrients. DOI PubMed
  4. Meta-analysisPapi A, Alfano F, Bigoni T, Mancini L, et al. (2024). N-acetylcysteine Treatment in Chronic Obstructive Pulmonary Disease (COPD) and Chronic Bronchitis/Pre-COPD: Distinct Meta-analyses.. Archivos de bronconeumologia. DOI PubMed
  5. Winterlind EL, Malone SG, Setzer MR, Murphy MA, et al. (2024). N-acetylcysteine as a treatment for substance use cravings: A meta-analysis.. Addiction biology. DOI PubMed
  6. Meta-analysisPeng TR, Lin HH, Tseng TL, Huang YH, et al. (2024). Efficacy of N-acetylcysteine for patients with depression: An updated systematic review and meta-analysis.. General hospital psychiatry. DOI PubMed
  7. Koh A, Wong T, Adiamah A, Sanyal S (2024). Systematic review and meta-analysis of the effect of N-acetylcysteine on outcomes after liver resection.. ANZ journal of surgery. DOI PubMed
Show 3 more references
  1. Huang C, Kuo S, Lin L, Yang Y (2023). The efficacy of N-acetylcysteine in chronic obstructive pulmonary disease patients: a meta-analysis.. Therapeutic advances in respiratory disease. DOI PubMed
  2. Kishi T, Sakuma K, Hatano M, Iwata N (2023). N-acetylcysteine for schizophrenia: A systematic review and meta-analysis.. Psychiatry and clinical neurosciences. DOI PubMed
  3. Nejati M, Dehghan P, Jamilian P, Zarezadeh M (2022). The effects of N-acetylcysteine on recovery biomarkers: A systematic review and meta-analysis of controlled trials.. Journal of food biochemistry. DOI PubMed