In just the past few months, the FDA has released several advisory notices to both doctors and the public about drugs linked to suicidal thoughts or actions, including Singulair, epilepsy drugs and the smoking-cessation drug Chantix. Reports have also been filed on antidepressants, the influenza drug Tamiflu and the acne medicine Accutane.
After concerns were first raised about possible links between antidepressants and suicide about four years ago, the FDA commissioned researcher Kelly Posner, the principal investigator at the Center for Suicide Risk Assessment at Columbia University in New York, to help determine any suicidal risk posed by medications. Her quantitative tools and questionnaires to assess suicide risk are being applied to drugs already on the market and those still in testing.
"We know that whether or not these drugs actually cause suicidal thought or action is a question we have to answer, but up until now, none of the clinical trials for the drugs were set up to address the question,’’ says Posner. "Either way we have to get the right answers. It’s critical to know about drugs that pose risk, but debunking false notions of risk is equally important to the public health.’’
Finding a link can present other issues. This became evident when the FDA, based on a review of antidepressant clinical trials, found a slight increase in suicidal thinking among children and young adults taking antidepressants such as Paxil and Prozac. The rate in those taking antidepressants was 4 percent, twice the rate of those taking a placebo. The information was added to the label of antidepressants within the last few years, pushing many doctors to stop prescribing the drugs for many of their patients.
Laughren says the FDA hopes that by using Posner’s methods, they may be able to find categories of people who might be at risk for suicide on a particular drug and more carefully determine who should stay clear of the drug and in whom it can safely be prescribed.
At least in theory, there are some possible explanations for why some of the drugs in question might be associated with suicidal thoughts or action, says Jason Noel, director of clinical pharmacy services at Rosewood Center in Owings Mills, Md., a residential facility for people with developmental disabilities. Singulair, for example, has a similar chemical pathway to steroids, which are drugs that can affect behavior and mood.
The FDA is conducting a safety review of Singulair, which is also used to treat asthma, that is expected to take about another eight months.
When Kate Miller of Queensbury, N.Y., filled a new allergy drug prescription for her 15-year-old son, Cody, last July, she hoped it would improve his bothersome allergy symptoms. Now, Miller is wondering whether a possible side effect of the drug, Singulair, caused Cody — who she describes as a happy, athletic teenager — to take his own life about a month later.
Last week, Kate Miller and her husband, David, met with FDA officials in the office of Congresswoman Kirsten Gillibrand (D-N.Y.), who is pushing to help find answers on Singulair and other drugs that have been linked to suicide.
Adding to the confusion of how to determine the possibility that a drug can cause suicidal thinking or action is the fact that suicide and suicidal thinking is, sadly, fairly common in the United States. Suicide is the fourth leading cause of death for adults between the ages of 18 and 65, according to the most recent data from the National Center for Health Statistics, accounting for about 26,500 deaths in that age group in 2005. For those ages 15 to 24, suicide is the third leading cause of death.
For all ages, suicide rates increased just under 1 percent between 2000 and 2005, but children and young adults ages 10 to 24 experienced an 8 percent increase between 2000 and 2004, following a decrease in the 15 years prior to 2000, according to the Centers for Disease Control and Prevention in Atlanta. Ileana Arias, head of the CDC’s National Center for Injury Prevention and Control, says the agency doesn’t have an explanation for the increase.