Effexor XR (venlafaxine hydrochloride) is a prescription medication used for treatment of depression and anxiety disorders. It is available in 37.5mg, 75mg and 150mg capsules and is usually taken once daily.
Venlafaxine blocks reuptake of serotonin and norepinephrine, which increases active levels of both in the brain.
Venlafaxine should not be taken with clozapine, since this combination increases the risk of seizures. Venlafaxine should not be taken with other medications that increase serotonin levels, including SSRIs and MAOIs, since this may lead to the development of a serious and potentially fatal condition known as serotonin syndrome.
Alcohol consumption should be avoided while taking venlafaxine, since it may increase risk of serious side effects. Caution is advised when taking venlafaxine while pregnant, since the effect of venlafaxine on fetal development is not clearly understood.
Common side effects include chest pain, chills, fever, pain, headaches, tachycardia, increased appetite, weight gain, confusion, abnormal thinking, vertigo, difficulty urinating and changes to the sense of taste.
Cessation of use may lead to withdrawal symptoms, especially if venlafaxine has been used for a long period of time. Symptoms of withdrawal include odd sensations resembling an electric shock, anxiety, dizziness, sweating, insomnia, nausea, vertigo and confusion.