Varenicline, also known by the brand name Chantix, has received a lot of attention because of potential risks of changes in behavior, hostility, agitation, depressed mood, suicidal thoughts and behavior, and attempted suicide. Certainly the use of varenicline in patients with serious psychiatric illness such as schizophrenia and bipolar disorder may result in worsening of their preexisting psychiatric illness, but varenicline can still be a relatively safe and effective medication in this population when used appropriately. Smoking in patients with bipolar disorder is often highly treatment refractory, and they may have made numerous previous attempts to quit with no success. Varenicline provides new hope for successful smoking cessation.