Mucolytic, Antidote for Acetaminophen Overdose, Antidote


N-Acetylcysteine Oral Capsule

N-Acetylcysteine Oral Tablet

acetylcysteine 600 MG Oral TabletGeneric

N-Acetylcysteine Inhalation Solution


Glutathione prodrug, Antidote for Acetaminophen Overdose, Mucolytic

What is NAC?

N acetylcysteine (NAC) is a supplemental form of the semi-essential amino acid cysteine. It is converted in the body to glutathione, an important antioxidant which prevents oxidative stress. The recommended dose is 600-900mg twice daily, but most people should be able to get enough cysteine from their diet without needing to supplement with NAC.

What is NAC used for?

NAC is used to detoxify the blood and internal organs. It is best known for its antioxidant and anti-inflammatory properties, which are used to treat a huge range of conditions from lung disease to mental health illnesses.

As well as being taken as a supplement, NAC is sometimes prescribed to reverse the effects of Tylenol (paracetamol, acetaminophen) overdose.

How does NAC work?

NAC removes toxins from the blood by increasing levels of antioxidants – particularly the antioxidant glutathione. We make cysteine from other amino acids that we get from the foods we eat, but some people’s diet is not nutritious enough to make adequate amounts themselves. In these people, or anyone with a medical condition inhibiting absorption, NAC works as an anti-inflammatory and to replenish antioxidants.

Antioxidants are important because they neutralize molecules called free radicals. Free radicals are unstable atoms that move around the body causing random, potentially damaging, chemical reactions. Neutralizing free radicals reduces the effects of their imbalance against antioxidants, known as oxidative stress, which can create a risk of diseases such as cancer.

Benefits of NAC

Your body cannot make NAC on its own, but it can make cysteine from other amino acids that we get from food. Foods high in protein are generally high in cysteine: salmon, chicken, yoghurt, eggs and sunflower seeds are great natural sources. For those that don’t eat enough cysteine-rich foods, NAC supplements can help them stay healthy. These come in capsule, inhaler, liquid or drop form. NAC has low bioavailability, meaning it is not absorbed well. For this reason, and as with most supplements, it is always best to get it naturally from your diet.

Conditions NAC may help

NAC for anxiety

Research shows NAC to be an effective treatment for multiple mental health illnesses. When used to treat anxiety, it has been found to reduce the frequency of uncontrollable, irrational thoughts – something that is prevalent in anxiety. The usual dose for anxiety is 2000mg per day, split across two or more intervals.

NAC for OCD and obsessive thoughts

Similar to anxiety, Obsessive-Compulsive Disorder (OCD) is characterized by uncontrollable emotions and thoughts. One study found NAC to be tolerable and effective alongside therapy for treating OCD. 2400-3000mg per day is the most common dose across studies.

NAC for depression

Research supports NAC tablets to be an effective treatment for depression alongside therapy, however, it is not well-supported enough to be prescribed as a treatment on its own. The recommended dosage for most psychiatric conditions is 2000-2400mg per day.

NAC for memory

In some studies NAC was shown to reduce the impacts of ageng, including memory loss. In Parkinson’s Disease, NAC was administered intravenously (50-150mg daily) or orally (1200-6000mg daily). In Alzheimer’s Disease, 600mg of NAC was administered orally per day. Both diseases were eased significantly with their respective NAC treatments.

NAC for trichotillomania and skin picking

Trichotillomania (hair-pulling) and excoriation (skin-picking) are symptoms of disorders often grouped with OCD, and NAC is an effective treatment for both, where 1200-2400mg was administered orally. The effectiveness of NAC for OCD-related illness comes from its ability to control glutamine levels. Glutamine is a neurotransmitter in the brain that controls a person’s ability to control their own behaviors.

NAC for COVID-19

Recent studies have suggested NAC as a treatment for COVID-19, because of its antioxidant and anti-inflammatory properties. As an infection that primarily affects the lungs, the effects of NAC on COVID are argued to be similar to its effects on other lung disorders. As a novel illness, more research is needed on COVID’s reaction with NAC.

NAC for cystic fibrosis

Cystic fibrosis, a hereditary disorder that can cause the lungs to fill with excess mucus, was the first reported medical condition treated with NAC. Clinical studies have shown 900mg of effervescent NAC three times a day to effectively improve lung function, relieving the symptoms of cystic fibrosis.


Chronic obstructive pulmonary disease (COPD) is a chronic lung disease where inflammation causes airway blockage and subsequent breathing difficulties. NAC works as an anti-inflammatory as well as to keep the lungs’ defense mechanisms working effectively. Studies have found that just 600mg of NAC taken orally per day can improve the symptoms of COPD.

NAC for bronchitis

The soothing, anti-inflammatory properties of NAC are great for treating lung disorders such as bronchitis. NAC increases glutathione levels, reducing oxidative stress, and breaks up mucus in the lungs, clearing airways and easing breath. Multiple studies have found 1200mg of NAC to be an effective treatment for bronchitis with airway obstructions, while 600mg is an adequate treatment for bronchitis without airway obstruction.

NAC for allergies

As with lung disease, the effects of allergies can be reduced with NAC supplements. NAC helps to reduce congestion and inflammation, so works well to unblock noses and airways. Some earlier studies found NAC to have antihistamine properties, but more recently it has been found to increase histamine levels. For that reason, it is not usually recommended for allergies alone.

NAC for acetaminophen overdose

Tylenol (acetaminophen, paracetamol) is a popular OTC pain relief, but excessive consumption can lead to liver damage, which can be fatal. If taken intravenously within 8 hours of Tylenol overdose, NAC produces glutathione that binds to the poison and reacts with it – sparing the cells that would have reacted otherwise. Studies have shown that around 600mg of NAC in tablet form can prevent death and even reduce damage to the liver in the case of Tylenol overdose.

NAC for grey hair

Grey hair, while not a medical problem that requires treatment, can be a symptom of heightened stress levels or another underlying health problem. If greying occurs early, it can sometimes be prevented by increasing glutathione levels. Taking NAC intravenously may reduce or even reverse greying of the hair, but this is only currently supported by studies on mice.

NAC for liver

NAC’s detoxifying and anti-inflammatory properties make it a great supplement for anyone with liver disease or damage. By reducing the strain of oxidative stress, NAC helps the cells in the liver to fight toxins and function healthily. A review found that up to 2g of NAC per kg of body weight improved liver symptoms in 85% of studies, but also highlighted the need for more rigorously controlled clinical trials. Daily, NAC can be taken orally to promote a healthy liver, but in an emergency (such as a drug overdose) an IV drip will be issued.

NAC for blood pressure

Multiple studies have found that 1.2-1.8g of NAC taken orally, daily can lower blood pressure. Most studies in this area also note that it is preferable to gain adequate cysteine levels from the diet, before attempting to supplement.


Polycystic ovary syndrome (PCOS) is a major cause of female infertility. Multiple studies have found that around 1800mg of NAC taken orally per day can improve the chance of getting pregnant and giving birth successfully. 1800mg of NAC daily can improve egg and embryo quality in females with PCOS. Additionally, unexplained female infertility can be improved with NAC supplements. 1.2g per day alongside other treatments was found to improve pregnancy rates in women classified as infertile.

NAC for endometriosis

NAC can effectively reduce and maintain the size of cysts in patients with endometriosis. One study found that 600mg three times daily was enough to be effective and produced no significant side effects.

NAC for histamine intolerance

NAC supplements may activate histamine production, however more random controlled clinical trials are needed to recommend its use.

NAC for obesity

Research has found NAC to be an effective anti-obesity treatment, but most studies are on mice. NAC has been found to improve metabolism, inflammation and oxidative damage in cases of obesity, however, more studies are needed to confirm its effectiveness in humans.

NAC for urinary tract infection (UTI)

NACs antioxidant properties make it useful for treating UTIs, but studies with human subjects are needed here also.

NAC for flu treatment

NAC might be an effective treatment for flu symptoms, easing the symptoms with its anti-inflammatory properties and preventing replication.

NAC typical dosage


600-1200mg, twice per day


Not yet specified, but studies range from 200mg 3 times a day to 2400mg per day

N-Acetylcysteine may diagnose:

N-Acetylcysteine contraindicated conditions:

N-Acetylcysteine desired effects:

  • Decreased Respiratory Secretion Viscosity
  • Increased Glutathione Concentration

N-Acetylcysteine drug classes:

  • Mucolytic
  • Antidote for Acetaminophen Overdose
  • Antidote

N-Acetylcysteine pharmacologic actions:

  • Expectorants
  • Antiviral Agents
  • Free Radical Scavengers

N-Acetylcysteine mechanism of action:

  • Reduction Activity
  • Free Radical Scavenging Activity
  • treatable

The content offered on is intended for informational purposes only and not as medical advice. For medical advice you should consult an appropriately licensed and qualified medical professional. If you are experiencing acute or distressing symptoms or life threatening symptoms you should immediately call 911 and/or go to the nearest emergency medical facility.

Copyright © Treatable 2022
Last updated: 1/27/2022, 12:53:09 PM