New report details additional Chantix side effects.
A non-profit agency called the Institute for Safe Medication Practices (ISMP) has released an analysis of the side effects of Chantix (varenicline), and the news is not good. They found that in the 4th quarter of 2007, Chantix accounted for 988 serious injuries, more than any other single medication. To put this in perspective, the median number of injuries reported per drug in that same quarter was five. This analysis is important because, while the FDA has issued a public health advisory about psychiatric side effects of Chantix (see TCPR March 2008), the agency did not describe the data in any detail. ISMP obtained and analyzed data for all adverse events reported since Chantix was approved in 2006. They found 227 reports of suicidal acts, 397 cases of possible psychosis, and 525 cases of hostility or aggression. In addition, they found many cases of seizures, cardiac arrhythmias, and accidents that were associated with Chantix use. As a result of this report, the FAA has banned Chantix use for air traffic controllers and pilots, while the Federal Motor Carrier Safety Administration has banned its use in truckers. (The ISMP report is available online at http://www.ismp.org/docs/vareniclineStudy.asp.)
TCPR’s Take: It is becoming increasingly clear that Chantix causes psychiatric symptoms in many people, and this latest data is making the drug look even more problematic. Smoking, too, is problematic, so this remains a very tricky risk/benefit analysis. The key is full disclosure of this data to your patients, and very close follow-up.
An approach to treating comorbid anxiety disorder and bipolar disorder.
How should we treat patients with both bipolar disorder and a comorbid anxiety disorder? The answer is not straightforward. Antidepressants, especially SSRIs and SNRIs are generally our first line medication for anxiety disorders, but they can sometimes destabilize patients with bipolar disorder. Benzodiazepines are fine, but they present their own potential problems with dependency and sedation. In this study, researchers enrolled patients with bipolar disorder who were stable on lithium, but who also had a specific DSM-4 anxiety disorder. 47 patients were randomly assigned to add-on treatment with either Zyprexa (N=24, mean dose 7.7 mg/day) or Lamictal (N=23, mean dose 96.7 mg/day). This was a single blind study, in which the patients did not know the identity of their pills, but the investigators did. After 12 weeks, both medications were helpful in decreasing anxiety scores on the Hamilton Anxiety Scale, but Zyprexa was significantly more effective than Lamictal. Lamictal had the unfortunate side effective of increasing anxiety in 8 of 23 patients (35%), vs. 0 of 24 on Zyprexa (Maina G, J Clin Psychiatry 2008;69:609-616).
TCPR’s Take: Zyprexa beat Lamictal, partly because the dose of Lamictal was titrated so slowly that more Lamictal patients dropped out before the end of the trial. Using the LOCF (last observation carried forward) approach, these scores at dropout were included in the final data analysis, making Lamictal look particularly bad. When only those patients who completed the trial were analyzed, there was no longer a statistically significant difference. The bottom line is that Zyprexa is likely to be more effective more quickly in anxious bipolar patients, but Lamictal will eventually catch up, if you can convince such patients to stay the course.