Some strong warnings have been issued by Health Canada over the stop-smoking pill Champix (in the U.S., the drug, generically known as varenicline tartrate, is called Chantix), which is sold by Pfizer Canada Inc., wrote The Globe and Mail.
The warning was issued by Pfizer and federal health officials following concerns that the popular smoking cessation drug is linked to “mood changes; hostility; suicidal behavior and serious, sometimes fatal, skin reactions.” Champix, the Pfizer Canada, Inc. brand must carry a boxed warning, indicating a serious safety issue or serious issue with adverse events exists, said The Globe and Mail; the U.S. Food and Drug Administration (FDA) required a similar warning since last year.
At that time, the FDA said psychiatric side effects seen among Chantix users included—at that time—98 reports of suicide and 188 reports of attempted suicide. While some reported psychiatric problems could have been the result of nicotine withdrawal, the FDA noted that many problems occurred while Chantix users were still smoking.
Health Canada stated that Champix is a prescription medicine used in combination with supportive counseling to help motivated adults quit smoking and that patients experiencing any of the following events—or caretakers and families observing the following—should stop the treatment and immediately contact a healthcare provider:
• Changes in mood or behavior including depressed mood, agitation, aggression, hostility, thoughts of self-harm, or harm towards others.
• Serious allergic reactions, including swelling of the face, lips, gums, tongue and throat that can cause trouble breathing, as well as skin reactions, including rash, swelling, redness, and peeling of the skin. This includes hypersensitivity reactions, such as angioedema (swelling under the skin that can be fatal) and serious skin reactions, including Stevens-Johnson syndrome and erythema multiforme.
Health Canada also warned patients to be aware that neuropsychiatric side-effects have occurred in patients taking Champix, regardless if those patients did or did not have a history of psychiatric disorder; alcohol could increase these risks. Expanded side effects such as sleepiness, dizziness, loss of consciousness, seizures, or difficulty concentrating, were discussed as having been observed in Chantix users.
To date, Health Canada has received over 1,200 reports of adverse reactions associated with Champix since its release in country in 2007, said The Globe and Mail. The following June, the department issued a public advisory warning consumers about some reactions patients taking Champix experienced related to behavior changes, hostility, and suicidal ideation, said The Globe and Mail; a reminder was sent January 2009 and the department announced plans to place a stricter warning on the drug.
Pfizer has long maintained Chantix/Champix’s safety and argues that such effects are often seen when people attempt to quit smoking. According to Pierre Martineau, director of medical affairs of cardiovascular and metabolic at Pfizer Canada, “Nicotine withdrawal symptoms are something that can cause neuropsychiatric adverse events,” quote The Globe and Mail. While the controversy over the drug’s safety and efficacy continue, Chantix’s association with psychiatric problems has spawned scores of product liability lawsuits.
