N-acetylcysteine (NAC) is an endogenous compound that is made from the amino acid L-Cysteine. It is typically used as an anti-aging supplement and to improve liver health and promote detoxification.
It is also believed to play a role in maintaining healthy hair, skin and nails. The correct N-acetylcysteine dosage to use will depend on the reason for taking this supplement
N-acetylcysteine is frequently taken to increase glutathione synthesis in the liver. This important anti-oxidant plays a number of roles throughout the body and has been implicated for slowing the aging process, protecting your organs from oxidative damage, reducing inflammation and possibly reducing the risk for numerous diseases including cancer.
In medical context, NAC doses are used to treat the symptoms of acetaminophen poisoning, bigender infertility, sulfur mustard-induced bronchiolitis, depression, cocaine withdrawal and more.



- Boosts glutathione & supports liver function
- Shown to increase endurance & reduce fatigue
- Fertility & higher sperm count in males
Taking N-Acetylcysteine Supplements
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NAC is known to be likely safe and is used widely in oral supplement form. It can be found in capsules or tablets as well as in Liver Detox supplements and drink mixes.
It is also possible to supplement with L-cysteine in pill form or by increasing consumption of foods that contain this amino acid. NAC is also sold as a prescription drug that has been approved by the FDA.
So long as appropriate N-Acetylcysteine dosages are used, side effects are rare. Adverse reactions are normally limited to diarrhea, headache, nausea and/or vomiting.
In rare cases, other side effects have been observed, including disturbances with pulmonary, cardiovascular, neuronal and musculoskeletal systems. Certain drug and herbal interactions may also occur.
N-acetylcysteine Dosages
The following N-acetylcysteine dosages are recommended commonly by medical doctors. Before taking this supplement, speak to your doctor to determine the right dosage for you.
Your doctor can also alert you to any negative interactions or contraindications for taking NAC supplements as well as other supplements that can complement the effects of this compound, including Alpha Lipoic Acid.
To treat sulfur-induced bronchiolitis, 600 mg doses are administered 2 or 3 times daily for up to 4 months. To combat chronic bronchitis, NAC has been administered in doses between 200 and 600 mg daily for periods up to 6 months. Also, some studies showed positive effects with time-released NAC tablets administered twice each day for 6 months.
600 mg NAC tablets were administered once each day for 6 months to improve the symptoms of chronic obstructive pulmonary disease (COPD). To treat acute respiratory infections, NAC is administered at a rate between 200 and 230 mg, 2 or 3 times each day, for periods between 6 and 15 days.
To increase glutathione synthesis inside the liver and counteract the poisonous effects of acetaminophen toxicity, a loading dose of 140 mg/kg of bodyweight is administered. This is followed by 70 mg/kg doses every 4 hours for 3 days. This dosage should not be used without doctor supervision and is intended for short-term use only.
Contrast mediated nephropathy (acute renal failure) has been improved with twice-daily N-acetylcysteine dosages up to 1200 mg each. Also, 600 mg doses have been administered twice daily with similar positive effects. Oral doses were administered for 7 days. Oral doses may be followed by intravenous injections at 600 mg twice daily for 2 days.
To treat addictions to gambling, N-acetylcysteine dosages of 600 mg daily have been administered. This dose is increased every 2 weeks until 1800 mg are being ingested daily. Treatments last for up to 14 consecutive weeks. To assist with the symptoms of cocaine withdrawal, N-acetylcysteine 600 mg tablets are administered every 12 hours for 48 hours.
To improve the symptoms of depression, NAC has been used in daily doses of 1 gram, taken twice each day for up to 24 weeks consecutively. There is limited research into the efficacy of NAC for depression treatment, but this is an interesting area for future study.
Taking 400 mg of NAC each day with breakfast is recommended for increasing appetite, especially when associated with high-altitude anorexia. No duration parameters have been noted at this dosage level.
Taking 2 daily 600 mg doses of NAC, beginning on either the second of the third day menstruation, has been shown to improve symptoms of female infertility.
Notably, these improvements were observed when using NAC is conjunction with clomiphene citrate. Also, risk of miscarriage is reduced when taking NAC at 600 mg daily, when coupled with folic acid supplementation.
Concerning male infertility, improvements have been demonstrated via once-daily 600 mg doses of NAC for periods up to 26 weeks.
N-acetylcysteine dosages between 600 mg and 1000 mg daily are used to treat cystic fibrosis. These amounts are divided into either 2 or 3 equal amounts, spaced evenly throughout the days.
Helicobacter pylori infections are treated with three daily doses of NAC 400 mg, in conjunction with traditional eradication therapies including lansoprazole and clarithromycin. Treatment lasts for ten days.
For pancreatitis treatment, two NAC 600 mg doses are administered: the first 24 hours before, and the second 12 hours before endoscopic retrograde cholangiopancreatography. This is followed with intravenous NAC doses of 600 mg, twice each day, for two days following the endoscopy procedure.
Oral administration of NAC has also been shown to improve schizophrenia symptoms, ulcerative colitis and Sjogren’s syndrome. Three daily doses of NAC 600 mg are used to alleviate the symptoms of epistaxis (nose bleeding).
600 mg N-acetylcysteine dosages are used to reverse hyperhomocysteinemia. Once-daily doses are administered for ten days. 600 mg effervescent tablets of NAC are used to prevent influenza symptoms. 2 tablets can be taken for up to 6 months.
Forms of N-acetylcysteine Supplements
The most common form of NAC supplement is an oral capsule. This supplement form is popular as an anti-aging compound, to promote liver health and to help detoxify the body of harmful toxins and chemicals.
In addition to being sold as a natural dietary supplement, N-acetylcysteine has also been approved as a prescription drug for the treatment of certain medical conditions. N-acetylcysteine dosages may also be delivered intravenously, intramuscularly, topically and/or via nebulized inhalation devices. When taking N-acetylcysteine to treat a medical condition, it should only be administered under the supervision of a physician.
Using NAC is known to be likely safe in the majority of cases. As long as you are using a safe N-acetylcysteine dosage, there are few side effects that have been observed. This is a natural compound that is found within the body, made from the dietary amino acid L-cysteine. There are possible interactions with various pharmaceuticals and botanicals. Pregnant and/or nursing women are not recommended to take NAC.
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Article last updated on: April 8th, 2018 by Nootriment
1 Comment
thanks for information on n acetyl cysteine.
wili you provide adequate intake value and upper intake level (UL) for the same?? please provide with reference.