Antismoking Drug Not Linked to Risk of Self-harm or Depression
Despite previous reports linking the antismoking drug Chantix® (varenicline) to suicide, suicidal thoughts, and depression, a new study published in the British Medical Journal shows that, if such a risk exists, it is likely to be very small.
Last July, the Food and Drug Administration (FDA) issued labeling requirements for Chantix and another antismoking drug, Zyban® (bupropion), to include its strongest safety message, warning that people taking the drugs should be closely watched for signs of suicidal thoughts, hostility, and depressed mood. According to the FDA, 98 suicides and 188 suicide attempts had been reported among people taking Chantix since the drug was approved for sale in the United States in 2006. (Fourteen suicides and 17 suicide attempts had been reported in users of Zyban.)
Despite the FDA’s warning, few large-scale studies had been conducted to accurately assess the mental health risks. Assessing risk is difficult because of the need to control for factors such as previous smoking habits and the presence of certain diseases. For example, people who smoke already have a two- to-threefold increased risk of suicide, since smoking is common among people with psychiatric illness, according to the researchers.
To clarify the risk, researchers from the University of Bristol and the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) compared the risk of self-harm among 80,660 patients, aged 18 to 95, who were prescribed a new course of any smoking-cessation product—Chantix, Zyban, or nicotine replacement products—between September 2006 and May 2008.
The researchers found “no clear evidence” that Chantix was associated with an increased risk of suicide or self-harm.
More studies are needed to further quantify the mental health risks associated with taking Chantix, but any risk should be weighed against the effectiveness of Chantix as an antismoking drug and the risks associated with continuing to smoke.