Deakin University medical researchers find potential new treatment for bipolar depression

Deakin University medical researchers have found that an antioxidant, N-acetylcysteine (NAC), is an effective treatment for bipolar depression.

Following the positive results experienced by 149 people with bipolar depression who took part in a two month trial, the researchers believe that NAC could be added to the treatment regimen of people with bipolar disorder.

"The people in our trial experienced significantly lower levels of depression and reported higher levels of quality of life and general functioning," said Dr Olivia Dean, a Deakin Medical School researcher based at Barwon Health in Geelong.

"There is currently no truly effective treatment for the depressive symptoms of bipolar disorder, with standard antidepressant medications having limited impact. Given the people in our trial had such positive results, and there are no major side-effects with NAC, it is a very promising option to be included with regular treatments. Larger trials are now needed to further test the benefits of NAC for people with bipolar depression. "

Bipolar disorder affects up to two per cent of Australians. People with the disorder suffer severe mood swings that can go from feeling low (depressed) to feeling high (manic).

"The depressive phase, which happens most often, is the most lethal as it is during this time that people with the disorder are at highest risk of suicide," Dr Dean explained.

"Given the stakes are so high it is imperative that we find effective treatments for the depressive phase of the disorder."

The researchers are now planning a larger study to definitively confirm the findings from this study. They are also embarking on a new trial with NAC that involves children aged 3-10 years with autism as there are many biochemical similarities between bipolar disorder and autism. Parents who are interested in this study can contact Kristi Villagonzalo on (03) 5226 7428.

The results of the trial will be published in the Journal of Affective Disorders.

About the study and NAC
149 people with bipolar disorder took 2000 mg per day of NAC along with their regular medications for eight weeks. On average, participants experienced a 46 per cent reduction in their depressive symptoms based on the Bipolar Depression Rating Scale. Similarly, on a measure of quality of life and of general functioning, significant improvements were reported.

N-acetylcysteine (NAC) is an antioxidant most commonly used to clear mucus from airways and to treat paracetamol overdose.

There are many ways that NAC could be working to improve the symptoms experienced by those with bipolar depression.

Oxidative stress, increased inflammation, changes in growth of nerve cells and alterations in signaling between nerve cells in the brain are all believed to play a role in bipolar disorder. NAC has mechanisms that target all of these factors. It is not entirely clear which of these mechanisms is responsible for improving mood symptoms, and further research is required to determine exactly how NAC works.