PlainPill
SupplementAnxietyMoodEnergy

NAC (n-Acetylcysteine)

People mainly take NAC (n-Acetylcysteine) for anxiety, mood, energy. Based on 35 first-hand reports and 1 meta-analyses & systematic reviews in the medical literature. Ranked #279 of 1,974 overall.

Compare with…Alternatives for anxiety
36
User score
Mixed
34% positive34% mixed6% negative26% unclear

Of reports that state an outcome, 46% are positive.

Clinical research
BModerate research base
1
meta-analyses
0
RCTs
132
papers

What NAC (n-Acetylcysteine) does, according to users

Of the people who reported each effect, the share who said it got better.

Anxiety90% of 10Mood80% of 10Energy71% of 7
3 more with fewer than 3 reports
Appetite100% of 2Focus100% of 2Memory100% of 1
betterno changeworse

What the research says

Systematic reviews and meta-analyses from PubMed, with their published conclusions.

BModerate research base

At least one meta-analysis, or 5+ randomized controlled trials. The grade measures how much human research exists — read the conclusions below for what it found.

Expert Rev Respir Med · 2021 · Meta-analysis / systematic review
Redox signaling and antioxidant therapies in acute respiratory distress syndrome: a systematic review and meta-analysis

Conclusion: Articles and conference abstracts about antioxidant therapies for patients with ARDS were identified in which the overall effect of each antioxidant therapy on the mortality of ARDS patients was summarized.Results: We identified 18 relevant studies that met the inclusion criteria, including 899 patients in the experimental group and 870 patients in the control group. The pooled results indicated that most antioxidant therapies could not improve all-cause mortality and might even be harmful in ARDS patients at low risk of death.Conclusion: Unclassified patients could not benefit from the antiox

PubMed 33928830 ↗

Dosage people report

As stated by users — not a recommendation. Follow the label or your doctor.

cycledas reported
600 mg3x daily
1200 mgdaily
600 mg2x daily
nightlyas reported
dailyas reported

Reported side effects

How often each side effect came up across all reports.

anhedonia ×3fatigue ×2drowsiness ×2stomach issues ×2anxiety ×2ulcers ×1increased acid ×1phlegm ×1

What users say

Verbatim quotes, shortened only — each links to the original discussion.

“NAC has helped me stay calm and reduce anxiety as well as gives me loads of energy if I am sleep deprived.”
Source discussion ↗
“NAC and L-Theanine helps a lot of my symptoms”
Source discussion ↗
“I tanked my iron with NAC. It's taken MONTHS to get my iron back up.”
Source discussion ↗
“You might want to try NAC”
Source discussion ↗
“I'm trying NAC for the first time and has basically turned off the tinitus that I have had going on in my brain for years.”
Source discussion ↗
Top discussions (5)

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User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 2, 2026. How we rate