Like Cymbalta, Effexor works by preventing the brain from reabsorbing the neurotransmitters serotonin and norepinephrine.

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The disease is associated with abnormal levels of norepinephrine and estradiol, hormones that are known to help regulate the immune system.

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Classified as a norepinephrine reuptake inhibitor, it is not a controlled substance.

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Anecdotal evidence suggested that venlafaxine, one of a newer class of antidepressants called selective norepinephrine reuptake inhibitors, could alleviate hot flashes, he explained.

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When you're tense, you get a rush of brain chemicals, like norepinephrine and cortisol, that cause you to hyperfocus "like a deer in the headlights, " says psychologist Lucy Jo Palladino.

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Also known as duloxetine, the new medicine is a follow-up to Prozac that works by keeping the brain from reabsorbing serotonin, as most antidepressants do, but also by targeting the reuptake of norepinephrine, which drugs like Prozac ignore.

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It is not the first drug to target both serotonin and norepinephrine--that honor goes to Effexor, a blockbuster made by Wyeth (nyse: WYE - news - people ) and put on the market around the same time as Prozac.

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