You may have seen something called “NAC” being sold in the supplement isle of your local pharmacy and wondered what exactly is NAC? The name is an abbreviation that stands for N-Acetyl Cysteine which is a stable form of the amino acid L-Cysteine. One of its most common medical uses is as a treatment for acetaminophen overdose. NAC protects the liver from acetaminophen overdose by boosting production of glutathione, an important antioxidant that helps protect the liver cells from toxicity.
NAC is also effective at reducing mucus viscosity (when given in an inhaled form) which is helpful for various respiratory conditions such as bronchitis and pneumonia. Besides just breaking up mucus there is also some evidence that NAC can help reduce inflammation in diseases like COPD (Chronic obstructive pulmonary disease).
Outside the hospital setting more and more people are looking to NAC to treat a variety of conditions. Some of these uses have scientific evidence supporting them and some have minimal evidence. First let’s look at some promising research regarding the use of NAC for psychiatric disorders. It has been shown that cysteine levels have an effect on the production of two important neurotransmitters, glutamate and dopamine. This means that in psychiatric disorders where there are abnormalities in these neurotransmitters NAC may play an important role in treatment. In one study 84 people with chronic schizophrenia where treated with an antipsychotic medication and either placebo or NAC. The group receiving NAC showed a greater improvement of symptoms over the placebo group. Similar positive results were seen in a double-blind placebo study of patients with bipolar disorder. Participants receiving NAC showed an improvement in their depressive symptoms that were significant compared to the placebo group.
While more research needs to be conducted before NAC would be considered a mainstream treatment for psychiatric disorders it does seem like a safe complimentary treatment for a variety of disorders including addiction and OCD as well as bipolar and schizophrenia.
Before adding any supplement to your diet however it is important to consider possible adverse effects. NAC does have a negative interaction with Nitroglycerin and the two should not be taken together. Also due to NAC’s ability to protect the liver some people use it as a hangover remedy after drinking. However, taken after consuming alcohol, NAC may actually increase liver damage. There is also a lack of data on the effects of taking NAC long term. If you are considering this supplement it is best to discuss the pros and cons with your doctor.