Pfizer: Chantix Does Not Increase Risks for Heart Attack and Depression By Charissa Echavez | Sep 08, 2015 10:13 PM EDT A new study emerges contradicting the previous belief that the smoking-cessation drug of Pfizer can increase the risk of heart attacks and depression. Furthermore, scientists even recommended the use of Chantix for people who need help in to quit smoking. Earlier studies revealed that after a few weeks of taking Chantix, a drug manufactured by Pfizer to help smokers quit smoking, occurrences of behavioral changes, depressed moods, and suicidal thoughts as well as seizures and heart attacks were reported. The Food and Drug Administration (FDA) itself asked the company to update and include these warnings in their label earlier this March. Pfizer collaborated with several researchers to study the claim. For 6 months, they traced 150,000 smokers in England who took varenicline (Chantix), or Champix in Europe. They categorized them into three: Group A with Chantix prescription, Group B with bupropion, an antidepressant and used also as an anti-smoking drug, and Group C with nicotine replacement therapy like patches and chewing gum. They found that users of the stop-smoking drug are no more likely to suffer a heart attack than the others. Furthermore, they were at a higher risk from neither depression nor suicide. Watch video Daniel Kotz, the co-author from Heinrich-Heine-University Dusseldork, said in a statement that "smokers typically lose three months of life expectancy for every year of continued smoking. Our research supports the use of varenicline as an effective and safe tool to help people quit." With this "extensive analysis," FDA should thus "review its safety warning in relation to varenicline as this may be unnecessarily limiting access to this effective smoking cessation aid," Aziz Sheikh of the University of Edinburgh's Centre for Medical Informatics said. Chantix being one of the top grossing stop-smoking drugs in the U.S. and Britain has generated a total revenue of $647 million last year. This is because the drug claims to reduce the craving and pleasurable effects of smoking especially to those who finds it difficult to quit. There are various ways to help a smoker stop smoking. Undergoing therapies and taking medications can be some. According to statistics in 2010, in every 10 smokers, there are seven of them who have a desire to quit smoking. In fact, to date, the number of former smokers exceeds the current smokers. If the current trend persists, smoking will claim around eight million lives per year.