Europe's drugs watchdog has issued a warning over suicidal ideations and attempts among patients taking stop-smoking medicine varenicline (Champix).
The European Medicines Agency issued the warning after monitoring varenicline since it was licensed for use in the European Union in September last year.
Its Committee for Medicinal Products for Human Use (CHMP) has analysed all adverse reactions to the drug.
At its meeting this month, the CHMP decided to warn doctors that depression has been reported in patients who are trying to stop smoking using varenicline.
Symptoms of this depression may include suicidal ideation and suicide attempts, the committee said. It requested that its manufacturer, Pfizer, revises product information accordingly to warn doctors and patients.
A spokesperson added: 'The EMEA will continue to keep this issue and take appropriate actions if further concerns arise.'