Anxiously Awaited News: Antidepressant Effectively Relieves Symptoms of Anxiety Disorder
June 20, 2000 -- For the first time, researchers have shown that the
antidepressant Effexor XR provides long-term relief from the disabling symptoms
of generalized anxiety disorder. This is promising news to the millions of
people in the United States who suffer from the condition.
Effexor XR had just received government approval in March as a treatment for
generalized anxiety, but that approval was based on studies lasting only eight
weeks. The new findings come from a six-month analysis that compares three
different doses of the drug to placebo. The study results, published in this
week's issue of the Journal of the American Medical Association, show
that patients achieved a lasting benefit from Effexor XR. Overall, 69% of those
on the drug had less anxiety, compared to 42% taking placebo.
It's estimated that generalized anxiety affects about 5% of the U.S.
population, and about two-thirds of the patients are women. Symptoms, which can
linger for six months or longer, include constant worry and anxiety about
ordinary problems and often masquerade as physical problems, which is why many
with generalized anxiety wind up getting treated by primary care
"[Generalized anxiety] is really a lifelong condition, and so in real
life I suspect ... patients are going to be indefinitely on antidepressant
treatment, much as there are people with chronic and recurring depression who
stay on it forever," lead study researcher Alan Gelenberg, MD, of the
University of Arizona Health Sciences Center, tells WebMD.
Gelenberg notes that using tranquilizers to control anxiety symptoms can
lead to abuse, and some other antidepressants haven't been adequately tested or
have limitations. Effexor XR increases the activity of two chemical messengers
in the brain, norepinephrine and serotonin. That may account for the drug's
ability to fight anxiety as well as depression.
"Despite the chronic nature of generalized anxiety, there are to date no
published ... studies demonstrating that ... therapy provides long-term ...
efficacy," write Gelenberg and colleagues. To prove this point, the
investigators set up a six-month study in 14 medical facilities around the
country. They divided approximately 250 patients into two groups -- one getting
Effexor XR, the other dummy pills.
Participants were allowed to increase or decrease their dose as needed,
depending on their reaction to the drug. About 20% of the patients in the trial
suffered nausea, the most common side effect, and patients taking monoamine
oxidase inhibitors for depression should avoid Effexor XR because of the danger
of drug interaction.
At the end of study, which was sponsored by Wyeth-Ayerst, the drug's
manufacturer, tests to measure anxiety showed that those taking Effexor XR were
much improved over the six-month period. Although some patients had improvement
in anxiety symptoms shortly after beginning to take the drug, the majority of
patients experienced improvements after taking the drug for two months.
Stephen Stahl, MD, a professor of psychiatry at the University of
California, San Diego, says that the study findings should send a clear message
to generalized anxiety sufferers who may be tempted to give up early in
treatment: "You can get much better from [generalized anxiety] ... if you