What Are the Benefits of NAC (N-acetyl Cysteine)?

NAC is a derivative of L-cysteine and it is used as an over-the-counter supplement to treat various health problems. The benefits of NAC include that it may be helpful for lung disease, acetaminophen poisoning, cancer, and autism.

N-acetyl cysteine is a nutritional supplement with a difficult name to remember and spell, but nonetheless, it’s built up a strong reputation within the past decade for helping people deal with issues that range from acetaminophen poisoning to lung disease. 

Learn more about the uses, benefits, and potential side effects of taking NAC and decide whether or not you're someone who may benefit from its effects. 

NAC is a derivative of L-cysteine, which is a non-essential amino acid. It’s used as an over-the-counter supplement to treat various health problems. Research shows that it can treat acetaminophen poisoning and clear up mucus caused by lung disease. 

As an antioxidant, it has potential anti-inflammatory and immune-boosting properties as well. 

Cysteine exists in several foods that are high in protein. Meats, sausages, yogurt, and oats supply this amino acid. Don’t get the two compounds confused, though: When most people talk about "cysteine" as a supplement, they are referring to N-acetyl cysteine. 

You can’t find NAC in food.

Lung diseases

Chronic obstructive pulmonary disease (COPD) causes long-term inflammation and mucus in the lungs. While some studies imply that NAC can be administered safely even at high doses to break up these patients’ lung congestion and reduce flare-ups of the disease, other studies don’t show significant results. 

Despite mixed results, it’s still a promising treatment for lung conditions, and it will probably be studied much more in the future.

Acetaminophen (Tylenol) poisoning

One of the original benefits of NAC was treating acetaminophen poisoning, and it’s still given to patients in hospitals for this purpose. 

If you think you have taken too much Tylenol either by accident or on purpose, though, it’s not a good idea to try to fix it by taking over-the-counter NAC. In this situation, you should immediately head to the closest emergency room or call an ambulance for help.

Repetitive behavior and irritability in cases of autism

Autism spectrum disorder often involves repetitive behaviors like rocking, hand flapping, jumping, or spinning. Among the many medical and behavioral interventions available to help a child with autism, there aren't many that reduce these behaviors. 

NAC, however, has shown promise, based on research concerned with decreasing repetitive behavior related to the autism spectrum.

Many children with autism have trouble transitioning to a new activity, and they might be upset or frustrated by a sudden change in routine. These outbursts may not be a big deal in a toddler, but they can turn into life-threatening situations when an adult with autism lashes out at someone else. 

A few studies thus far have shown that NAC may be able to help decrease the irritability that can lead to this type of aggression. 

Cancer treatment side effects

Cancer can be stressful to have and to treat. It can be difficult to know what to do if you feel like your cancer treatment is causing more side effects than benefits, and this frustration might lead some patients to try natural supplements and other forms of complementary medicine. 

Because NAC works for acetaminophen poisoning, many experts think it may reduce the harmful effects of some cancer treatments as well. Specifically, NAC might help decrease the side effects and toxicity of common cancer medications.

Overall, the jury’s still out on whether it’s a good idea to take NAC for cancer because it protects cells from damage — and there’s a risk that it will protect the healthy cells as well as the cancerous ones. If you’re interested in taking NAC, speak with your doctor about the relevant research. 

Despite marketing campaigns that seem to be everywhere, antioxidants aren’t always the miracle substance the claims make them out to be, and it's hasty to suggest that taking NAC is a good idea for everyone with these conditions. This isn’t to say that you shouldn’t take NAC at all, but you should be careful. There’s research to suggest that it’s not ideal to give cancer patients a lot of antioxidants.

Overall, NAC supplements are safe for most people when taken as directed. Bear in mind: Though it’s often used to prevent poisoning and toxic effects from cancer treatments, it can have unpleasant side effects of its own. 

Look out for the following symptoms when you are taking NAC:

• Stomach issues like nausea, diarrhea, and constipation.
• A rash or increased blushing.
• Low blood pressure.
• Headaches, ringing in the ears, and flu-like symptoms like fever and chills (at very high doses).
• Tiredness.

While NAC is sold over the counter and is relatively safe for most people, there are dangers associated with taking it at the wrong dosage or for the wrong condition. There’s a lot we don’t know about NAC yet. 

Stay on the safe side and don’t take NAC if you are in one of the following categories:

• You’re pregnant or breastfeeding. There isn’t enough research to determine whether taking NAC during these times is safe or not.
• You’re taking medicine that could interact with NAC like nitroglycerin and carbamazepine. Don’t stop taking any medication in order to take NAC instead. Ask your doctor what you should do if you want to try NAC. Your doctor may want to adjust your prescription.
• You have heart, kidney, or liver disease, which can affect how much NAC is safe for you to take.

Do you want to add NAC to your healthcare plan? Unlike some other popular, over-the-counter supplements, there is research that backs up using NAC for specific conditions. Ask your doctor for dosage information and learn more about whether or not NAC is safe for you.