Our pick for your dose
- Buy on Amazon for Nutricost NAC 600 mg
600 mg a capsule, lowest cost per 600 mg
Nutricost NAC 600 mg $0.10 for 1 capsule (600 mg) · $0.20 for 2 (1,200 mg)
Nutricost’s label says 1 capsule a day (600 mg), about $0.10. Many trials used 2 capsules’ worth (1,200 mg), about $0.20 a day. Ask your doctor before you take more than the label says. It is on no public testing list.
Each brand’s own list price, checked October 15, 2026; prices on Amazon differ. Other NAC for your dose ↓
A summary of published research and product labels, not medical advice. NAC can interact with nitrate medicines. Talk to your doctor or pharmacist first.
How much NAC per day?
The bottles we compared say to take 600 to 1,800 mg a day: from 1 capsule a day (Nutricost) up to 3 a day (Life Extension, Pure Encapsulations). Trials used 600 to 3,000 mg a day. Many used 1,200 mg: 600 mg twice a day.
There is no official daily amount (no RDA) for NAC, because it is not a nutrient you need from food. So the two guides are what your label says and what trials used. Both are below.
What NAC has been studied for
This is the NAC dosage each study used: how much a day, how it was split and for how long. These are amounts studied, not advice. What each study found is in our NAC guide.
| What was tested | Amount a day | How it was split | How long |
|---|---|---|---|
| COPD and chronic bronchitis flare-upsCazzola 2015; Zheng 2014 | 600 to 1,200 mg | 600 mg once or twice a day | Months, up to 1 year |
| Hair pullingGrant 2009 | 1,200 to 2,400 mg | Not given in the summary | 12 weeks |
| Skin pickingGrant 2016 | 1,200 to 3,000 mg | Not given in the summary | 12 weeks |
| Cannabis (no effect)Gray 2017; Gray 2025 | 2,400 mg | 1,200 mg twice a day | 12 weeks |
The OCD and PCOS reviews did not give amounts in their summaries, so they are not in this table.
| Item | Value (mg) |
|---|---|
| One NAC capsule | 600 mg |
| COPD flare-ups | 600–1,200 mg |
| Hair pulling | 1,200–2,400 mg |
| Skin picking | 1,200–3,000 mg |
| Cannabis (no effect) | 2,400 mg |
Is 600 mg enough?
The research does not agree, so here are both sides.
Says the dose matters
A 2015 review of 13 COPD studies found fewer flare-ups with NAC. Its authors suggest 600 mg a day for chronic bronchitis without blocked airways, and 1,200 mg or more a day when the airways are blocked (Cazzola 2015).
Says the dose did not matter
A 2019 Cochrane review of 38 trials of mucus-thinning medicines, NAC among them, found that the type or dose did not seem to change the result (Poole 2019).
Trials for hair pulling and skin picking used more: 1,200 to 3,000 mg a day. The largest single COPD trial gave 1,200 mg a day for a year (Zheng 2014).
What this means when you buy: one 600 mg capsule is the low end of what trials used. Many trials used 1,200 mg a day. Some labels (NOW) say 2 capsules a day; Nutricost’s says 1. Ask your doctor before you take more than the label says.
How to split NAC doses
The 1-year COPD trial gave 1,200 mg as one 600 mg tablet twice a day (Zheng 2014). The cannabis trials gave 1,200 mg twice a day (Gray 2017; Gray 2025). Splitting is simple:
- 600 mg a day: 1 capsule, any time of day.
- 1,200 mg a day: 1 capsule (600 mg) in the morning and 1 in the evening.
- 2,400 mg a day: trials that used it gave 1,200 mg twice a day. That is 4 capsules, more than the most any label we read suggests (3). Only with your doctor.
In 10 healthy people, the share of NAC that reached the blood went up with the dose (200, 600 and 1,200 mg). Taking 600 mg twice a day for 5 days did not build up NAC in the blood (Borgström 1990).
How many capsules a day? NAC products priced per day
Most NAC capsules are 600 mg, but not all. Thorne’s are 500 mg, so 600 mg takes 2. Toniiq’s are 650 mg. Pick an amount and a product to see how many capsules that is.
Find your capsules
| Product | NAC each | Label says | For 600 mg a day | For 1,200 mg a day |
|---|---|---|---|---|
| BulkSupplements NAC powder | 600 mg | 600 mg (about ¼ teaspoon) up to three times a day | 1 scoop$0.055 a day | 2 scoops$0.11 a day |
| Nutricost NAC 600 mgOur pick | 600 mg | 1 capsule a day | 1 capsule$0.10 a day | 2 capsules$0.20 a day |
| Toniiq NAC 1300 | 650 mg | 2 capsules a day on an empty stomach | 1 capsule (650 mg)$0.12 a day | 2 capsules (1,300 mg)$0.25 a day |
| Life Extension NAC 600 mg | 600 mg | 1 capsule one to three times a day | 1 capsule$0.19 a day | 2 capsules$0.38 a day |
| NOW NAC 600 mg | 600 mg | 1 capsule twice a day | 1 capsule$0.19 a day | 2 capsules$0.38 a day |
| Jarrow N-A-C Sustain 600 mg | 600 mg | 1 tablet once or twice a day, on an empty stomach if possible | 1 tablet$0.37 a day | 2 tablets$0.73 a day |
| Thorne NAC 500 mg | 500 mg | 1 capsule two or three times a day | 2 capsules (1,000 mg)$0.73 a day | 3 capsules (1,500 mg)$1.10 a day |
| Pure Encapsulations NAC 600 mg | 600 mg | 1 capsule one to three times a day, between meals | 1 capsuleNo list price | 2 capsulesNo list price |
BulkSupplements is a powder: one 600 mg scoop is about ¼ teaspoon. Pure Encapsulations has no list price we could check.
Where your NAC comes from decides whether it counts
NAC inside a blend is usually a small amount. We checked 900 NAC labels in the NIH label database, and 482 say how much NAC they hold. Only 94 of those are plain NAC. The other 388, about 4 in 5, are liver formulas, detox blends, pre-workouts and amino acid mixes with NAC as one of many ingredients.
| Where the NAC is | Labels | Typical NAC a serving | Under 600 mg |
|---|---|---|---|
| Sold as NAC | 94 | 600 mg | Most are 600 mg |
| Inside a blend | 388 | 100 mg | 94% |
A blend’s NAC is real, but a typical blend gives 100 mg, a sixth of one plain capsule, and 62% of blends have under 200 mg. Don’t count it toward an NAC dose. If NAC is what you want, a plain 600 mg capsule is the simple choice. See a real blend label, marked up.
NAC gummies dosage
Most NAC is sold as capsules, so check a gummy’s label before you count on it. Of the 900 NAC labels we checked, most were capsules, powders or tablets; only 1 was a gummy, and it did not say how much NAC it held. None of the 8 products we compare is a gummy.
On a gummy label, check three things:
- The NAC line on the Supplement Facts panel, in mg. If there is no mg number for NAC, you can’t know how much you get.
- The serving size. “500 mg per serving” may mean 2 or 3 gummies. Divide to get the NAC in one gummy.
- How many gummies make 600 mg. Divide 600 by the NAC in one gummy. At 150 mg a gummy, that is 4 gummies for one capsule’s worth. Check the sugar on the panel too.
How to take NAC
- With or without food. No trial we read compared taking NAC with or without food. Follow your label: some say to take it on an empty stomach (Jarrow, Toniiq) or between meals (Pure Encapsulations). If it upsets your stomach, take it with food.
- Split larger amounts. For 1,200 mg or more, take half in the morning and half in the evening, as the trials did.
- Expect a sulfur smell. NAC contains sulfur, so capsules can smell like rotten eggs. That is normal, not a sign the bottle has gone bad.
- Give it time. Trials measured results after weeks or months, not days.
Other NAC for your dose
Our pick, Nutricost NAC 600 mg, is at the top. One button for each other product we compared:
- Check price for Toniiq NAC 1300
1,200 mg or more in one serving
Toniiq NAC 1300 $0.12 per 600 mg · $0.25 for 2 capsules (1,300 mg)
The only one of the 8 with 1,200 mg or more in one serving. Label: 2 capsules a day on an empty stomach.
- Check price for Jarrow N-A-C Sustain 600 mg
A slow-release tablet
Jarrow N-A-C Sustain 600 mg $0.37 per 600 mg (1 tablet)
Made to release part of its NAC quickly and part slowly. The only slow-release option of the 8. Label: 1 tablet once or twice a day, on an empty stomach if possible.
- Check price for Thorne NAC 500 mg
On a public testing list
Thorne NAC 500 mg $0.44 per 600 mg · $0.37 for 1 capsule (500 mg)
On NSF/ANSI 173. Each capsule is 500 mg, so 600 mg takes 2. Label: 1 capsule two or three times a day.
- Life Extension NAC 600 mg: 600 mg a capsule, $0.19 per capsule. $11.25 for 60 capsules. Check price for Life Extension NAC 600 mg
- NOW NAC 600 mg: 600 mg a capsule with 25 mcg of selenium, $0.19 per capsule. $47.99 for 250 capsules. Check price for NOW NAC 600 mg
- BulkSupplements NAC powder: Powder: 600 mg is about ¼ teaspoon, $0.055 per 600 mg. Check price for BulkSupplements NAC powder
- Pure Encapsulations NAC 600 mg: 600 mg a capsule, 90 capsules. No list price: the brand sells nothing on its own site. Check price for Pure Encapsulations NAC 600 mg
Each brand’s own list price, checked October 15, 2026. Best NAC supplements · every NAC compared
Frequently asked questions
How much NAC should I take per day?
Most labels say 600 to 1,800 mg a day, and many trials used 1,200 mg. There is no official daily amount. Ask your doctor what fits you.
Is 600 mg of NAC enough?
It is the low end of what trials used, and the two big reviews disagree on whether more helps. Both sides.
Is 1,200 mg of NAC a day too much?
It is the amount the largest COPD trial gave for a year, and side effects were about as common as on a dummy pill (29% vs 26%; Zheng 2014). Some labels (NOW) say 1,200 mg a day; Nutricost’s says 600 mg.
Can I take NAC 1,200 mg twice a day?
That is 2,400 mg a day, more than any label we read suggests (1,800 mg). Two cannabis trials used it, and the hair-pulling trial went up to it. Stomach side effects were more common at that amount (Gray 2025). Only with your doctor’s advice.
What does “NAC 600 mg BID” mean?
BID means twice a day: 600 mg in the morning and 600 mg in the evening, 1,200 mg a day.
How do I take NAC?
Swallow it with water and follow the directions on your bottle. Talk to your doctor or pharmacist if you take any medicine.
With or without food?
Follow your label; take it with food if it upsets your stomach.
How much NAC is in a gummy?
It varies, so read the NAC line on the panel. How to check a gummy label.
Does NAC interact with medications?
Yes, with nitrates such as nitroglycerin, and ask about blood thinners. All the cautions.
Related guides
- NAC supplement guide — what the trials found, side effects, and why NAC left Amazon and came back
- Best NAC supplements — products compared by dose, testing and cost
- What NAC costs — prices by product
- Glutathione supplements — the antioxidant your body makes from cysteine
Sources
- Cazzola M, et al. Influence of N-acetylcysteine on chronic bronchitis or COPD exacerbations: a meta-analysis. Eur Respir Rev. 2015. PubMed 26324807
- Poole P, et al. Mucolytic agents versus placebo for chronic bronchitis or chronic obstructive pulmonary disease. Cochrane Database Syst Rev. 2019. PubMed 31107966
- Zheng JP, et al. Twice daily N-acetylcysteine 600 mg for exacerbations of COPD (PANTHEON). Lancet Respir Med. 2014. PubMed 24621680
- Grant JE, et al. Trichotillomania trial. Arch Gen Psychiatry. 2009. PubMed 19581567
- Grant JE, et al. Skin-picking (excoriation) trial. JAMA Psychiatry. 2016. PubMed 27007062
- Gray KM, et al. Drug Alcohol Depend. 2017. PubMed 28623823. Gray KM, et al. Neuropsychopharmacology. 2025. PubMed 39910268
- Borgström L, Kågedal B. Dose dependent pharmacokinetics of N-acetylcysteine after oral dosing to man. Biopharm Drug Dispos. 1990. PubMed 2328298
- Horowitz JD, et al. Combined use of nitroglycerin and N-acetylcysteine. Circulation. 1988. PubMed 3127076
- Label directions and warnings: NIH Dietary Supplement Label Database (Life Extension 328582, NOW 313864, Jarrow 323064, Nutricost 306361, Pure Encapsulations 277781, Thorne 336347, BulkSupplements 311094) and Toniiq’s own label. 900 NAC labels from the same database; our analysis. List prices: each brand’s own page, read October 15, 2026. Testing lists searched October 15, 2026.
This page is for information. It is not medical advice.