Each year, two per cent to four per cent of Americans experience the debilitating emotional and physical symptoms of generalized anxiety disorder (GAD). Given the chronic nature of this condition, it is critical that patients with GAD are treated with an effective long-term therapy. The goal of therapy should be to virtually eliminate their symptoms and prevent relapse. Effexor XR (venlafaxine HCl), a serotonin-norepinephrine reuptake inhibitor (SNRI) and the first antidepressant approved for the treatment of GAD, remains the only antidepressant indicated for the short- and long-term treatment of patients with this disorder.

"The excessive uncontrollable worry associated with generalized anxiety disorder can greatly disrupt an individual's daily life, which is why it is critical to virtually eliminate the symptoms of this chronic, debilitating condition," says Norman Sussman, MD, professor of psychiatry, New York University School of Medicine. "Effexor XR is effective in helping patients with GAD achieve and sustain virtual elimination of symptoms, while also reducing the likelihood they will suffer from a relapse."

According to three pooled analyses of 1,841 GAD patients in five double-blinded studies, Effexor XR was effective in treating GAD patients' emotional and physical symptoms and was equally effective regardless of the initial severity of physical symptoms. Moreover, 767 GAD patients treated with Effexor XR, and followed up for six months, demonstrated continued improvement across the spectrum of symptoms beyond their first eight weeks of therapy.

"Effexor XR has a proven efficacy and safety profile through a wealth of published data and its use in over 8.4 million patients with GAD, depression, and social anxiety disorder (SAD) since its approval in 1997," said Victoria Kusiak, MD, vice president of Global Medical Affairs and North American medical director, Wyeth Pharmaceuticals. "Because GAD often coexists with depression, patients who have both conditions should work with their physician to find a medication, such as Effexor XR, that's proven to be effective in improving and virtually eliminating the symptoms of both GAD and depression."

SNRIs, such as Effexor XR, affect the level of two chemicals in the brain, serotonin and norepinephrine, thought to play a key role in depression, GAD, and SAD. Correcting the imbalance of these two chemicals may help relieve the symptoms of these conditions.

For GAD patients with mostly emotional symptoms, Effexor XR delivered significantly greater rates of remission (defined as a Hamilton Rating Scale for Anxiety [HAM-A] total score =7) versus placebo for emotional symptoms(p<0.001) and physical symptoms (p<0.05) after eight weeks of treatment, as well as for both types of symptoms after 24 weeks of treatment (p<0.001), as measured using the HAM-A, according to a pooled analysis of 1,841 patients in five double-blind studies. Furthermore, for GAD patients with mostly physical symptoms, Effexor XR delivered significantly greater rates of remission versus placebo of emotional symptoms (p<0.05) and physical symptoms (p<0.001) at week eight, as well as for both emotional and physical symptoms at week 24(p<0.05).

GAD is one of the most common anxiety disorders, thought to be due to a chemical imbalance in the brain marked by a constant and exaggerated sense of worry that has lasted for at least six months. GAD often coexists with depression, a condition that affects approximately 19 million Americans annually. With the right treatment, it is possible for people with GAD and/or depression to improve or virtually eliminate their symptoms, get back to being themselves and re-engage in their favorite activities.

Effexor XR is a structurally novel antidepressant chemically unrelated to any other available antidepressant. The most common adverse events reported in Effexor (venlafaxine HCl) short-term placebo-controlled depression trials and Effexor XR short-term placebo-controlled depression, generalized anxiety disorder (GAD), and/or social anxiety disorder (SAD) trials (incidence (10 per cent and (2x that of placebo) were anorexia, asthenia, constipation, dizziness, dry mouth, ejaculation problems, impotence, insomnia, nausea, nervousness, somnolence, and sweating.

Effexor/Effexor XR is contraindicated in patients taking monoamine oxidase inhibitors (MAOIs). Treatment with venlafaxine is associated with sustained increases in blood pressure (BP) in some patients. Regular BP monitoring is recommended. Abrupt discontinuation or dose reduction has been associated with discontinuation symptoms. Patients should be counseled on possible discontinuation symptoms and monitored while discontinuing the drug; the dose should be tapered gradually.

Effexor XR was discovered and developed by Wyeth Pharmaceuticals, the pharmaceutical division of Wyeth. The product is also marketed by Wyeth Pharmaceuticals. The FDA approved the immediate-release formulation in 1993; the extended-release (XR) formulation was approved in 1997. These medications are available only by prescription.