NAC
What is NAC?
N-acetylcysteine (NAC) is a supplement that contains the amino acid cysteine, which is a precursor to glutathione, a powerful antioxidant in the body (1). NAC is available over-the-counter and is commonly used to treat acetaminophen overdose and to loosen thick mucus in people with chronic obstructive pulmonary disease (COPD) or cystic fibrosis (2). It is also used as a dietary supplement to support liver health, boost immunity, and reduce inflammation (3).
Dosage
The recommended dosage of NAC varies depending on the condition being treated and individual factors. For acetaminophen overdose, the recommended dose is 140 mg/kg followed by 70 mg/kg every 4 hours for 17 doses (2). For other uses, the typical dose ranges from 600 to 1800 mg per day, divided into two or three doses (1). It is important to follow the directions on the product label and consult a doctor or pharmacist for any clarification.
Side Effects
NAC is generally considered safe when taken in recommended doses. However, it may cause side effects such as nausea, vomiting, diarrhea, constipation, heartburn, headache, drowsiness, dizziness, dry mouth, and fever (1)(3). High doses of NAC may cause more serious side effects, such as liver damage, bleeding disorders, and bronchospasm (1). People with asthma or bleeding disorders should use NAC with caution.
Interactions
NAC may interact with certain medications, such as nitroglycerin, isosorbide dinitrate, and ACE inhibitors, which are used to treat heart disease and high blood pressure (1). NAC may also interact with activated charcoal, which is used to treat poisoning, and with chemotherapy drugs (1). It is important to tell your doctor about all the medications and supplements you take before using NAC.
Time of Day and With or Without Food
There is no specific time of day that NAC should be taken, and it can be taken with or without food (1).
Human Studies
NAC has been studied for its potential therapeutic benefits in various conditions, including acetaminophen overdose, COPD, cystic fibrosis, liver disease, and mental health disorders (1)(3). However, more research is needed to fully understand its effectiveness and safety in these and other conditions.
To summarize, N-acetylcysteine (NAC) is a supplement that contains the amino acid cysteine and is commonly used to treat acetaminophen overdose and to loosen thick mucus in people with COPD or cystic fibrosis. It is also used as a dietary supplement to support liver health, boost immunity, and reduce inflammation. NAC is generally safe when taken in recommended doses, but may cause side effects and interact with certain medications. There is no specific time of day that NAC should be taken, and it can be taken with or without food. While NAC has been studied for its potential therapeutic benefits in various conditions, more research is needed to fully understand its effectiveness and safety.
Citations:
(1) https://www.frontiersin.org/articles/10.3389/fphar.2022.828565
(2) https://ubccriticalcaremedicine.ca/academic/jc_article/Acetaminophen Poisoning (Jan-30-14).pdf
(3) https://emedicine.medscape.com/article/820200-treatment
(4) https://www.dovepress.com/n-acetylcysteine-overdose-after-acetaminophen-poisoning-peer-reviewed-fulltext-article-IMCRJ
(5) https://www.ncbi.nlm.nih.gov/books/NBK537183/
(6) https://www.fda.gov/media/71436/download