Neither varenicline nor bupropion are associated with an increased risk of suicide, self-harm or depression, according to a UK study comparing users of both drugs with patients attempting to quit with nicotine replacement therapy.
The study, published today in the BMJ, looked at 119,546 adults who had used a smoking cessation product between 2006 October 2011. The researchers from the University of Bristol then assessed the rate of treated depression, self-harm and suicide in the 26.2 % of patients prescribed varenicline, the 5.6% prescribed bupropion and the 68.2% using nicotine replacement therapy.
They found no evidence of an increased risk of treated depression or suicidal behaviour for patients prescribed with varenicline or bupropion compared to those taking NRT
Concerns that these drugs may increase the risk of suicide led to safety warnings by both the Medicines and Healthcare products Regulatory Agency and the US Food and Drug Administration.