Taking Champix to quit smoking may induce depression

BRENDAN TREMBATH: A pill designed to help smokers quit is causing concern because of reports that it led to suicides and depression among some patients in the United States. The prescription drug sold as Champix was launched in Sydney today and will be available on the Pharmaceutical Benefits Scheme from January. The drug has been available in the US and Europe for over a year where there have been reports of depressive symptoms in some patients. Just last week the European Medicines Agency asked the pharmaceutical company Pfizer to update its product safety information. The safety information has been changed in Australia too to include a warning that people with mental illness should take the drug with caution.

Jennifer Macey reports.

JENNIFER MACEY: With the new year fast approaching, it's time to think about New Years resolutions. And giving up cigarettes will be top of the list for many smokers. So it's no coincidence that the drug company Pfizer today launched the latest anti-smoking drug, Champix.

Nick Zwar is a professor of general practice at the University of New South Wales. He says the drug works by blocking the effect of nicotine on the brain.

JENNIFER MACEY: And the drug is recording good results. In two studies, about a quarter of all Champix users were still off cigarettes a year after taking the drug. But there are growing concerns about the drug's possible side effects. There have been reports in the UK and the US that some patients have become depressed and some have committed suicide during the treatment. Of the 20,000 Champix users in Britian, 50 people reported depression and suicidal thoughts

NICK ZWAR: Sure. Well, they're clearly important concerns. The smoking sensation itself can be a cause of mood changes and feelings of depression, and that's been recognized for some time. The other thing to say is that this medicine has not been used to any large degree in people with a history of mental health problems such as depression or psychosis, so it's not recommended, or it's certainly cautioned about use in those people.

JENNIFER MACEY: The pharmaceutical company Pfizer says depression did not emerge as a side effect during the clinical trials of the drug.

Dr Bill Ketelbey is the senior medical director with Pfizer Australia.

BILL KETELBEY: Clearly very unusual, very rare side effects may not be picked up in the standard clinical research program that is undertaken leading up to the registration of a product. And only side effects that are picked up through standard surveillance of patients who are on products under the care of their doctors over the months and years after its launch, only those side effects will be picked up through the standard surveillance, and that's why we undertake the surveillance.

JENNIFER MACEY: Drug regulatory authorities in the US and Europe are investigating the reports of depression and suicide. Just last week the European Medicines Agency asked Pfizer to update its product safety information to include a warning that people with a history of mental illness should inform their doctor. Pfizer's Dr Ketelbey says this warning is also in the Australian leaflet.

BILL KETELBEY: The prescribing information in Australia has already been changed to include a statement that doctors should be aware that the side effects have been reported in patients on Champix who are ceasing smoking, and the same information has now been included in the European product information.

JENNIFER MACEY: But Associate Professor Renee Bittoun from the Brain and Mind Research Institute doubts there's a link between Champix and depression.

RENEE BITTOUN: Probably 40 per cent of all cigarettes smoked in Australia are smoked by people with depression. So smoking causes depression and depression causes smoking, so it is a bit of a circular event, I'm afraid. With regard to suicide, there's also a link with depression. We do know that smokers have many other co-morbidities, many other medical problems. So unfortunately, with regard to smoking and any medications, it's really predicted that, there are going to be a group of people who a - are depressed, b - may consider suicide, and also, quitting smoking exacerbates the problem, so smoking causes depression causes smoking, and quitting also can exacerbate depression. It's a symptom of withdrawal. Now, sometimes those symptoms of withdrawal just abate very quickly and sometimes they take a little while to get over. Most of the time it goes away.

BRENDAN TREMBATH: Associate Professor Renee Bittoun from the Brain and Mind Research Institute in Sydney ending that report by Jennifer Macey.

Side Effects of Champix

Side effects that have been reported to date include the following:

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  Vomitting and nausea


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  Headaches


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  Sleep disturbances and atypical dreams


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  Gas (wind)


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  Changes in the way food tastes (Dysgeusia)


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  Constipation

Of the above side effects, the most commonly reported one is nausea. If you get any other side effects that you think may be attributable to Champix, let your doctor know straight away. The less common side effects are detailed on the leaflet in the tablet packet.

It is not yet known whether or not it is safe to use Champix alongside nicotine replacement products such as chewing gum and patches.

Contraindications

Champix has not been studied in children and should not be taking by young people who are under 18 years of age.

What does my doctor need to know?

Your doctor needs to know:

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  if you suffer from kidney problems or you are on dialysis. It may be appropriate for you to receive a lower dose.


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  if you are pregnant. The effects of Champix on the foetus are not known and it would be better if you gave up smoking before getting pregnant.


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  if you are breast feeding. Champix may pass into breast milk and other ways of feeding your baby may be appropriate if you are currently taking the drug,


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  All medicines and herbal pills that you are taking, whether they are prescription drugs or no