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Antidepressants are a class of drugs that reduce symptoms of depressive disorders by correcting chemical imbalances of neurotransmitters in the brain. Chemical imbalances may be respo"...
Effexor (venlafaxine hydrochloride) is indicated for the treatment of major depressive disorder.
The efficacy of Effexor in the treatment of major depressive disorder was established in 6-week controlled trials of adult outpatients whose diagnoses corresponded most closely to the DSMIII or DSM-III-R category of major depression and in a 4-week controlled trial of inpatients meeting diagnostic criteria for major depression with melancholia (see Clinical Trials).
A major depressive episode implies a prominent and relatively persistent depressed or dysphoric mood that usually interferes with daily functioning (nearly every day for at least 2 weeks); it should include at least 4 of the following 8 symptoms: change in appetite, change in sleep, psychomotor agitation or retardation, loss of interest in usual activities or decrease in sexual drive, increased fatigue, feelings of guilt or worthlessness, slowed thinking or impaired concentration, and a suicide attempt or suicidal ideation.
The efficacy of Effexor XR in maintaining an antidepressant response for up to 26 weeks following 8 weeks of acute treatment was demonstrated in a placebo-controlled trial. The efficacy of Effexor in maintaining an antidepressant response in patients with recurrent depression who had responded and continued to be improved during an initial 26 weeks of treatment and were then followed for a period of up to 52 weeks was demonstrated in a second placebo-controlled trial (see Clinical Trials). Nevertheless, the physician who elects to use Effexor/Effexor XR for extended periods should periodically re-evaluate the long-term usefulness of the drug for the individual patient.
DOSAGE AND ADMINISTRATION
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 (see PRECAUTIONS, General, Use in Patients with Concomitant Illness).
Treatment of Pregnant Women During the Third Trimester
Neonates exposed to Effexor, other SNRIs, or SSRIs, late in the third trimester have developed complications requiring prolonged hospitalization, respiratory support, and tube feeding (see PRECAUTIONS). When treating pregnant women with Effexor during the third trimester, the physician should carefully consider the potential risks and benefits of treatment. The physician may consider tapering Effexor in the third trimester.
Dosage for Patients with Hepatic Impairment
Given the decrease in clearance and increase in elimination half-life for both venlafaxine and ODV that is observed in patients with hepatic cirrhosis and mild and moderate hepatic impairment compared to normal subjects (see CLINICAL PHARMACOLOGY), it is recommended that the total daily dose be reduced by 50% in patients with mild to moderate hepatic impairment. Since there was much individual variability in clearance between subjects with cirrhosis, it may be necessary to reduce the dose even more than 50%, and individualization of dosing may be desirable in some patients.
Dosage for Patients with Renal Impairment
Given the decrease in clearance for venlafaxine and the increase in elimination half-life for both venlafaxine and ODV that is observed in patients with renal impairment (GFR = 10 to 70 mL/min) compared to normals (see CLINICAL PHARMACOLOGY), it is recommended that the total daily dose be reduced by 25% in patients with mild to moderate renal impairment. It is recommended that the total daily dose be reduced by 50% in patients undergoing hemodialysis. Since there was much individual variability in clearance between patients with renal impairment, individualization of dosing may be desirable in some patients.
Dosage for Elderly Patients
No dose adjustment is recommended for elderly patients on the basis of age. As with any antidepressant, however, caution should be exercised in treating the elderly. When individualizing the dosage, extra care should be taken when increasing the dose.
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. In one study, in which patients responding during 8 weeks of acute treatment with Effexor XR were assigned randomly to placebo or to the same dose of Effexor XR (75, 150, or 225 mg/day, qAM) during 26 weeks of maintenance treatment as they had received during the acute stabilization phase, longer-term efficacy was demonstrated. A second longer-term study has demonstrated the efficacy of Effexor in maintaining an antidepressant response in patients with recurrent depression who had responded and continued to be improved during an initial 26 weeks of treatment and were then randomly assigned to placebo or Effexor for periods of up to 52 weeks on the same dose (100 to 200 mg/day, on a b.i.d. schedule) (see Clinical Trials). Based on these limited data, it is not known whether or not the dose of Effexor/Effexor XR needed for maintenance treatment is identical to the dose needed to achieve an initial response. Patients should be periodically reassessed to determine the need for maintenance treatment and the appropriate dose for such treatment.
Discontinuing Effexor (venlafaxine hydrochloride)
Symptoms associated with discontinuation of Effexor, other SNRIs, and SSRIs, have been reported (see PRECAUTIONS). Patients should be monitored for these symptoms when discontinuing treatment. 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.
Switching Patients To Or From A Monoamine Oxidase Inhibitor
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 (see CONTRAINDICATIONS).
Effexor® (venlafaxine hydrochloride) Tablets are available as follows:
25 mg, peach, shield-shaped tablet with “25” and a “W” on one side and “701” on scored reverse side.
NDC 0008-0701-08, bottle of 60 tablets in unit of use package.
37.5 mg, peach, shield-shaped tablet with “37.5” and a “W” on one side and “781” on scored reverse side.
NDC 0008-0781-08, bottle of 60 tablets in unit of use package.
50 mg, peach, shield-shaped tablet with “50” and a “W” on one side and “703” on scored reverse side.
NDC 0008-0703-07, bottle of 30 tablets in unit of use package.
75 mg, peach, shield-shaped tablet with “75” and a “W” on one side and “704” on scored reverse side.
NDC 0008-0704-07, bottle of 30 tablets in unit of use package.
100 mg, peach, shield-shaped tablet with “100” and a “W” on one side and “705” on scored reverse side.
NDC 0008-0705-07, bottle of 20 tablets in unit of use package.
The appearance of these tablets is a trademark of Wyeth Pharmaceuticals.
Store at controlled room temperature 20° to 25°C (68° to 77°F) in a dry place.
Dispense in a well-closed container as defined in the USP.
The unit of use package is intended to be dispensed as a unit.
Distributed by: Wyeth Pharmaceuticals Inc, A subsidiary of Pfizer Inc, Philadelphia, PA 19101. Revised March 2012
Last reviewed on RxList: 6/22/2012
This monograph has been modified to include the generic and brand name in many instances.
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