Nutricost N-Acetyl L-Cysteine (NAC) 600 mg, 180 Capsules
4.6(14,744)
$15.95
600 mg is the unit every trial used, twice a day. The most-bought NAC on Amazon and the cheapest per gram.
Buy on AmazonAmazon price on Sep 18, 2026.
Buy N-acetylcysteine
Products that match the form and dose used in the studies. Umbral earns a commission on some purchases; the order never changes because of it.
Moderate
600 mg twice daily (1200 mg/day) is the dose used in the large COPD trials. Lower 'antioxidant' doses have no respiratory outcome data.
Ratings, prices and photos were read from Amazon on Sep 18, 2026. Amazon prices change; the current one is on the product page.
As an Amazon Associate, Umbral earns from qualifying purchases. Product data is provided by Amazon and may change; ratings and prices shown are Amazon’s, not Umbral’s. Recommendations are based on the evidence grade and the form used in trials, never on commission.
NOW Supplements NAC 600 mg with Selenium & Molybdenum
4.6(21,224)
$21.85
Twenty-one thousand ratings, the most-reviewed NAC here. The selenium and molybdenum support the same detox pathway rather than muddying the test.
Buy on AmazonAmazon price on Sep 18, 2026.
Pure Encapsulations NAC 600 mg, 90 Capsules
4.7(3,974)
$38.50
The highest-rated of the three and hypoallergenic. In Mexico NAC is sold as a drug (Fluimucil and generics), which is the better supply route if you are there.
Buy on AmazonAmazon price on Sep 18, 2026.
Browse all options on Amazon
Prefer to compare yourself? This opens Amazon’s full selection for this supplement, filtered to the form we recommend.
See all on AmazonWhat to look for
- ✓N-acetylcysteine 600 mg capsules or effervescent tablets, pharmaceutical grade. In Mexico it is sold as a drug (Fluimucil and generics), which is the preferable supply route.
- ✓600 mg twice daily (1200 mg/day) is the dose used in the large COPD trials. Lower 'antioxidant' doses have no respiratory outcome data.
- ✓Third-party tested (USP, NSF, Informed Sport)
What to avoid
- ✕Proprietary blends that hide the dose per ingredient
- ✕Unstandardised extracts with no active-compound percentage
Safety notes
- · Nausea, vomiting and diarrhoea are the most common oral adverse effects.
- · Can trigger bronchospasm in some people with asthma or hyperreactive airways.
- · Rare anaphylactoid/hypersensitivity reactions, mainly with intravenous use.
As an Amazon Associate, Umbral earns from qualifying purchases. Product data comes from Amazon and may change; ratings and prices are Amazon's, not Umbral's. Suggestions are based on the science and the form used in studies, never on commission.
Umbral is a wellness product, not a medical device. It does not diagnose, treat, cure or prevent any disease. Supplement information is educational; talk to a clinician before starting anything, especially if you are pregnant, under 18, managing a condition or taking medication.
These statements have not been evaluated by the Food and Drug Administration.