Effexor, common uses
Effexor (venlafaxine hydrochloride) is indicated for the treatment of major depressive disorder. The mechanism of the antidepressant action of venlafaxine in humans is believed to be associated with its potentiation of neurotransmitter activity in the CNS.
Effexor (Venlafaxine), brand name Vandral Retard by Wyeth, comes as a capsule, 150 mg., to take by mouth.
The recommended starting dose for Effexor is 75 mg./day, administered in two or three divided doses, taken with food. Depending on tolerability and the need for further clinical effect, the dose may be increased to 150 mg./day. If needed, the dose should be further increased up to 225 mg./day. When increasing the dose, increments of up to 75 mg./day should be made at intervals of no less than 4 days. In outpatient settings there was no evidence of usefulness of doses greater than 225 mg./day for moderately depressed patients, but more severely depressed inpatients responded to a mean dose of 350 mg./day. Certain patients, including more severely depressed patients, may therefore respond more to higher doses, up to a maximum of 375 mg/day, generally in three divided doses.
It is generally agreed that acute episodes of major depressive disorder require several months or longer of sustained pharmacological therapy beyond response to the acute episode. It is not known, however, whether or not the dose of Effexor needed for maintenance treatment is identical to the dose needed to achieve an initial response. Individuals should be periodically reassessed to determine the need for maintenance treatment and the appropriate dose for such treatment.
At least 14 days should elapse between discontinuation of an MAOI and initiation of therapy with Effexor. In addition, at least 7 days should be allowed after stopping Effexor before starting an MAOI.
If you miss a dose, take it as soon as remembered if it is within an hour or so. If you do not remember until later, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.
Adverse reactions, some of which were serious, have been reported in patients who have recently been discontinued from a monoamine oxidase inhibitor (MAOI) and started on Effexor, or who have recently had Effexor therapy discontinued prior to initiation of an MAOI. These reactions have included tremor, myoclonus, diaphoresis, nausea, vomiting, flushing, dizziness, hyperthermia with features resembling neuroleptic malignant syndrome, seizures, and death. In individuals receiving antidepressants with pharmacological properties similar to venlafaxine in combination with a monoamine oxidase inhibitor, there have also been reports of serious, sometimes fatal, reactions. For a selective serotonin reuptake inhibitor, these reactions have included hyperthermia, rigidity, myoclonus, autonomic instability with possible rapid fluctuations of vital signs, and mental status changes that include extreme agitation progressing to delirium and coma. Some cases presented with features resembling neuroleptic malignant syndrome. Severe hyperthermia and seizures, sometimes fatal, have been reported in association with the combined use of tricyclic antidepressants and MAOIs. These reactions have also been reported in patients who have recently discontinued these drugs and have been started on an MAOI. Therefore, it is recommended that Effexor not be used in combination with an MAOI, or within at least 14 days of discontinuing treatment with an MAOI. Based on the half-life of Effexor, at least 7 days should be allowed after stopping Effexor before starting an MAOI.
Individuals with major depressive disorder, both adult and pediatric, may experience worsening of their depression and/or the emergence of suicidal ideation and behavior, whether or not they are taking antidepressant medications, and this risk may persist until significant remission occurs.
Individuals being treated with antidepressants should be observed closely for clinical worsening and suicidality, especially at the beginning of a course of drug therapy, or at the time of dose changes, either increases or decreases. Consideration should be given to changing the therapeutic regimen, including possibly discontinuing the medication, in patients whose depression is persistently worse or whose emergent suicidality is severe, abrupt in onset, or was not part of the individual’s presenting symptoms.
A major depressive episode may be the initial presentation of bipolar disorder. It is generally believed that treating such an episode with an antidepressant alone may increase the likelihood of precipitation of a mixed/manic episode in patients at risk for bipolar disorder. Prior to initiating treatment with an antidepressant, individuals should be adequately screened to determine if they are at risk for bipolar disorder.
Venlafaxine treatment is associated with sustained increases in blood pressure in some individuals.
Abrupt discontinuation or dose reduction of venlafaxine at various doses has been found to be associated with the appearance of new symptoms including agitation, anorexia, anxiety, confusion, coordination impaired, diarrhea, dizziness, dry mouth, dysphoric mood, fasciculation, fatigue, headaches, hypomania, insomnia, nausea, nervousness, nightmares, sensory disturbances, somnolence, sweating, tremor, vertigo, and vomiting.
Individuals should be monitored for these symptoms when discontinuing treatment with Effexor. A gradual reduction in the dose rather than abrupt cessation is recommended whenever possible. If intolerable symptoms occur following a decrease in the dose or upon discontinuation of treatment, then resuming the previously prescribed dose may be considered. Subsequently, the physician may continue decreasing the dose but at a more gradual rate.
The safety and efficacy of venlafaxine therapy in combination with weight loss agents, including phentermine, have not been established.
Effexor should be used cautiously by individuals with a history of mania.
Hyponatremia and/or the syndrome of inappropriate antidiuretic hormone secretion may occur with venlafaxine. This should be taken into consideration in patients who are, for example, volume-depleted, elderly, or taking diuretics.
Mydriasis has been reported in association with venlafaxine. Patients with raised intraocular pressure or at risk of acute narrow angle glaucoma should therefore be monitored.
Effexor should be used cautiously in patients with a history of seizures and it should be discontinued in any patient who develops seizures.
Measurement of serum cholesterol levels should be considered during long-term treatment of Effexor.
Effexor, like all antidepressants, should be used with caution by individuals with renal impairment.
Notify your physician if you become pregnant or intend to become pregnant during therapy of Effexor. Effexor should be used during pregnancy only if clearly needed.
Notify your physician if you are breast-feeding an infant. Because of the potential for serious adverse reactions in nursing infants from Effexor, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
The risk of using venlafaxine in combination with other CNS-active drugs has not been systematically evaluated. Caution is therefore advised if the concomitant administration of venlafaxine and such drugs is required.
Based on the mechanism of action of venlafaxine and the potential for serotonin syndrome, caution is advised when venlafaxine is co-administered with other drugs that may affect the serotonergic neurotransmitter systems, such as triptans, serotonin reuptake inhibitors, or lithium
Effexor, possible side effects
The most frequently observed side effects associated with the use of Effexor are asthenia, sweating, nausea, constipation, anorexia, vomiting, somnolence, dry mouth, dizziness, nervousness, anxiety, tremor, and blurred vision as well as abnormal ejaculation/orgasm and impotence in men.
Anxiety, agitation, panic attacks, insomnia, irritability, hostility, impulsivity, akathisia, hypomania and mania, have been reported in adult and pediatric patients being treated with antidepressants for major depressive disorder as well as for other indications, both psychiatric and nonpsychiatric.
If you notice other effects not listed above, contact your doctor.
If overdose of Effexor is suspected, contact your local poison control center or emergency room immediately.
Effexor, additional information
Keep Effexor in a tightly closed container and out of reach of children. Store Effexor at room temperature and away from excess heat and moisture (not in the bathroom).
The above information is intended to supplement, not substitute for, the expertise and judgment of your physician, or other healthcare professional. It should not be construed to indicate that use of Effexor is safe, appropriate, or effective for you.
Consult your health care professional before you