SSRIs and SNRIs do not carry the same side effects as some of the older antidepressants, such as tricyclics or monoamine oxidase inhibitors (MAOIs), which makes them more appealing to doctors and patients. Patients who are on MAOIs, for example, also have to follow a special diet. This is not required of patients who take SSRIs or SNRIs.
SSRIs and SNRIs both inhibit the re-absorption of serotonin, a neurotransmitter that is thought to play a role in controlling anxiety, mood, sleep and appetite. SSRIs basically ensure that there is more serotonin in the brain, which is thought to reverse depressive symptoms and stabilize the patient's mood.
In addition to increasing the serotonin in the brain, SNRIs also inhibit the re-absorption of norepinephrine, a neurotransmitter that is believed to play a role in sleep and alertness. Whereas SSRIs affect the level of serotonin in the brain, SNRIs affect the level of both serotonin and norepinephrine.
READ MORE EFFEXOR PPHN LEGAL NEWS
Currently, Effexor is listed by the US Food and Drug Administration (FDA) as Pregnancy Category C, meaning animal studies indicate a risk to the fetus but human studies have not indicated whether the risk involved in stopping medication is greater than the risk of birth defects.