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NOW Extra Strength (1000mg) NAC (N-Acetyl Cysteine)


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Info: 120 Tablets (1000 mg)

This formula is temporarily unavailable from the manufacturer. Please see AOR NAC, Protocol NAC (with co-factors), and Pure Encapsulations NAC. Not looking for tablets? See Canadian Protein's NAC Powder.

NAC has proven antioxidant, anti-inflammatory, and immune-modulating benefits that may be beneficial for both treatment and prevention of respiratory conditions.

Product Notes:

N-Acetyl Cysteine (NAC) is a stable form of the non-essential amino acid L-Cysteine, which is a necessary component for forming the potent antioxidant glutathione, and contains sulfur, which acts as a stabilizer for the formation of protein structures.

Considered the most powerful endogenous (made in our body) antioxidant, glutathione acts inside our cells (unlike vitamin C which acts outside cells), helping to eliminate free radicals while supporting the immune system. A natural detoxifier, glutathione can prevent neurological damage, and may help slow down the aging process. You can increase glutathione levels by regular exercise (not high intensity) and with dietary supplement precursors.

As a precursor to glutathione, NAC has been used for decades to treat acetaminophen overdose (which can be liver toxic) and to loosen thick mucus in the lungs. NAC can suppress viral replication and reduce inflammation, with studies proving it significantly decreases influenza frequency, and the duration and severity of most symptoms. In addition, NAC can reduce the incidence of pneumonia and improve lung function.

Is NAC banned in Canada or the USA?

The FDA in the United States is currently debating how to classify N-Acetyl Cysteine in that country. Manufacturers and regulators are working to decide which rules apply, and what NAC products may be available to consumers.

N-Acetyl Cysteine isn't currently facing the same regulatory issues in Canada. NAC supplements are reviewed and (when approved) licensed by Health Canada as natural health products. Both of these NAC formulas are licensed.

Naming Conventions

NAC goes by a number of different names and variations in spelling, including N-Acetyl-L-Cysteine, Acetylcysteine (or N-Acetylcysteine), and many brand names, but they all refer to a derivative of the dietary amino acid l-cysteine, with the molecular formula: C5H9NO3S. This NOW Foods Extra Strength formula contains 1,000 mg of NAC per tablet, more than what's available in many competing products.

Related Products: See AOR NAC, Pure Encapsulations NAC, and Protocol NAC.


Each Capsule of 600 mg NAC (Health Canada Natural Product Number: 80006038) contains:

600 mg N-Acetyl Cysteine
50 mcg Molybdenum (from Sodium Molybdate)
25 mcg Selenium (as L-Selenomethionine)

Non-medicinal ingredients: Veg. Capsule (hypromellose, water), Stearic Acid (vegetable source) and Citric Acid.

Each Tablet of Extra Strength 1000 mg NAC (NPN: 80052274) contains:

1000 mg N-Acetyl Cysteine

Non-medicinal ingredients: Cellulose, Silica, Stearic Acid, Tablet Coating (hypromellose, cellulose, stearic acid, water).

Suggested Usage:

600 mg version: Adults: take 1 capsule daily, with a protein-containing meal.

Extra Strength version: Adults: Take 1 tablet daily with meals.

Store in a cool, dry place.


600 mg version: Do not use NOW Foods NAC if you suffer from cystinuria/cystine kidney stones, or if you are pregnant or breastfeeding. Consult a healthcare practitioner prior to use if you are taking nitroglycerin, acetaminophen, iron supplements, or if you have gout. Consult a healthcare practitioner for use beyond 6 months.

Extra Strength version: Consult a healthcare practitioner prior to use if you are pregnant or breastfeeding, or if you have kidney stones.

Supporting Science:

Rasmussen JB, Glennow C. "Reduction in days of illness after long-term treatment with N-acetylcysteine controlled-release tablets in patients with chronic bronchitis." European Respiratory Journal. 1988 Apr.

Zhongcheng Shi, Carlos A Puyo. "N-Acetylcysteine to Combat COVID-19: An Evidence Review." Therapeutics and Clinical Risk Management. 2020; 16: 1047-55.

UPC / Barcode: 733739801852