Effexor XR is part of a class of drugs called serotonin-norepinephrine reuptake inhibitors, or SNRIs for short. SNRIs, such as Effexor XR, act on specific chemicals within the brain known as serotonin and norepinephrine. Serotonin and norepinephrine are two of several chemicals used to send messages from one nerve cell to another.
As a message travels down a nerve, it causes the end of the cell to release serotonin or norepinephrine. The serotonin or norepinephrine enters the gap between the first nerve cell and the one next to it. When enough serotonin or norepinephrine reaches the second nerve cell, it activates receptors on the cell and the message continues on its way. The first cell then quickly absorbs any serotonin or norepinephrine that remains in the gap between cells. This is called "reuptake."
Normally, this process works without any problems. But when the levels of serotonin or norepinephrine become unbalanced, it can cause a variety of conditions, including depression. Effexor XR helps to block the reuptake of serotonin and norepinephrine so more remains in the space between the brain's nerve cells. This gives the serotonin and norepinephrine a better chance of activating the receptors on the next nerve cell.
Effexor XR Effects
There have been several studies looking at the effects of Effexor XR for a variety of conditions.
Effexor XR for Depression
Studies have shown Effexor XR to be effective at treating depression in adults. In these studies, people taking Effexor XR had more improvement in their depression symptoms than people who did not take Effexor XR. Also, long-term studies showed that Effexor XR is also effective at preventing depression relapse.
Effexor XR for Generalized Anxiety Disorder
Three studies have looked at Effexor XR as a treatment for generalized anxiety disorder. In one short-term (eight weeks) study and two long-term (six months) studies, people taking Effexor XR showed greater improvements in their anxiety symptoms than people who did not take Effexor XR.
Effexor XR for Panic Disorder
In studies of Effexor XR for panic disorder, people taking Effexor XR were more likely to be free of panic attacks than people who did not take Effexor XR. Also, Effexor XR was effective at preventing panic disorder relapses.
Written by/reviewed by: Kristi Monson, PharmD;Arthur Schoenstadt, MD
Last reviewed by: KristiMonson, PharmD;
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