Effexor (Venlafaxine) Indications and Dosage

anxiety
depression
diabetic neuropathy _†
fibromyalgia _†
headache _†
hot flashes _†
menopause _†
neuropathic pain _†
panic disorder
premenstrual dysphoric disorder (PMDD) _†
social phobia (social anxiety disorder)

_† non-FDA-approved indication

Venlafaxine Indications and Dosage

For the treatment of major depression:
Oral dosage (immediate-release tablets):
Adults: 75 mg/day PO given in 2 - 3 divided doses. If needed, doses may be increased by 75 mg/day PO at intervals >= 4 days. In outpatient settings, a maximum dosage of 225 mg/day PO is recommended. In the institutional setting, the maximum dosage should not exceed 375 mg/day PO, given in 3 divided doses.
Oral dosage (extended-release capsules, e.g., Effexor XR® ):
Adults: Initially, 75 mg PO once daily. Alternatively, an initial dose of 37.5 mg PO once daily can be given for 4 - 7 days to allow the patient to adjust to the medication before increasing to 75 mg/day. If needed, the dose may be increased by 75 mg/day at intervals >= 4 days, up to 225 mg/day.

For the treatment of anxiety disorders:
NOTE: Anxiety disorders are often chronic conditions; consider continuation of venlafaxine in patients who demonstrate a therapeutic response. Maintain therapy at the lowest effective dosage and periodically reassess to determine the need for continued treatment.

for general anxiety disorder (GAD):
Oral dosage (extended-release capsules, e.g., Effexor XR® ):
Adults: Initially, 75 mg PO once daily. Alternatively, an initial dose of 37.5 mg PO once daily can be given for 4 - 7 days to allow the patient to adjust to the medication before increasing to 75 mg/day. If needed, the dose may be increased by 75 mg/day at intervals >= 4 days, up to 225 mg/day.

for social phobia (social anxiety disorder):
Oral dosage (extended-release capsules, e.g., Effexor XR® ):
Adults: Initially, 75 mg PO once daily. Alternatively, an initial dose of 37.5 mg PO once daily can be given for 4 - 7 days to allow the patient to adjust to the medication before increasing to 75 mg/day. If needed, the dose may be increased by 75 mg/day at intervals >= 4 days, up to 225 mg/day.

For the treatment of panic disorder (with or without agoraphobia):
Oral dosage (extended-release capsules, e.g., Effexor XR® ):
Adults: Initially, 37.5 mg PO once daily for 7 days. After the first week, dose may be increased to 75 mg/day PO, with subsequent weekly dose increases of 37.5 - 75 mg/day PO to a maximum dose of 225 mg/day PO. Although a dose-response relationship for effectiveness in patients with panic disorder was not clearly established in fixed-dose studies, certain patients not responding to 75 mg/day PO may benefit from dose increases. Titrate in increments of up to 75 mg/day PO and at intervals of not less than 7 days. In one randomized, placebo-controlled trial, venlafaxine ER was not associated with a greater number of patients free from full-symptom panic attacks. However, venlafaxine ER was associated with lower mean panic attack frequency and a greater number of patients free from limited-symptom panic attacks, higher response and remission rates, and improvements in anticipatory anxiety, fear, and avoidance. In 2 randomized, controlled, pivotal trials conducted by the manufacturer, the percentage of patients free of full-symptom panic attacks on the Panic and Anticipatory Anxiety Scale (PAAS) was found to be significant vs. placebo. Patients also exhibited a significantly longer time to relapse, defined as 1) having 2 or more full-symptom panic attacks per week for 2 consecutive weeks or 2) discontinuing the study due to loss of effectiveness as determined by the investigators.

For the treatment of hot flashes _† :

for the treatment of hot flashes _† in women with breast cancer experiencing symptoms of menopause _† :
Oral dosage (immediate-release tablets):
Adult females: 37.5 - 75 mg/day PO reduced the weekly incidence of hot flashes by up to 60% in women with breast cancer (i.e., women in whom HRT contraindicated) in one study. This dosage is lower than the typical dosages for antidepressant effect; however, higher doses do not improve efficacy against hot-flashes and are not as well tolerated.

for the treatment of men with prostate cancer experiencing hot flashes _† secondary to androgen-depravation therapy:
Oral dosage (immediate-release tablets):
Adult males: Based on initial open-label studies, a dosage of 12.5 mg PO twice daily reduces the daily incidence of hot flashes in roughly 63% of patients. This dosage is lower than the typical dosages used for antidepressant effect. Further studies are needed.

For the treatment of pain syndromes including neuropathic pain _† , diabetic neuropathy _† , headache _† , and fibromyalgia _† :
Oral dosage:
Adults: Initially, 37.5 - 75 mg PO per day. The usual maximum dosage required is 75 mg PO twice daily of the regular release formulation or 150 mg PO once daily of the extended-release formulation. However, in some instances, higher dosages may be necessary and the dosage should be titrated to clinical response.

For the treatment of premenstrual dysphoric disorder (PMDD) _† according to the criteria of the DSM-IV:
Oral dosage:
Adult females: 50 - 200 mg/day PO has been used. Initiate at 50 mg/day PO for the first cycle, then titrate upward if needed. Adverse events such as nausea, insomnia, and dizziness are typically mild and transient. The potential for using cyclic luteal phase administration (i.e., during the 14 days prior to menses) has yet to be defined.

Maximum Dosage Limits:

Adults: 375 mg/day PO for immediate-release tablets; 225 mg/day PO for Effexor XR® .

Elderly: 375 mg/day PO for immediate-release tablets; 225 mg/day PO for Effexor XR® .

Adolescents: Safe and effective use has not been established.

Children: Safe and effective use has not been established.

Patients with hepatic impairment:
For moderate hepatic impairment the initial daily dose should be reduced by 50%. Clearance in cirrhotic patients shows considerable individual variability, and greater dosage reductions may be necessary.

Patients with renal impairment:
Because patients with renal impairment show considerable individual variability in clearance, doses should be individualized.
CrCl 10 - 70 ml/min: reduce total daily dose by 25 - 50%.
CrCl < 10 ml/min: reduce total daily dose by 50%.

Intermittent Hemodialysis:
Reduce total daily dose by 50%; the dose should be withheld until dialysis is completed. Because patients with renal impairment show considerable individual variability in clearance, doses should be individualized.

[ Last revised: 12/1/2005 10:37:00 AM ]

References
_{. Loprinzi Cl et al. Venlafaxine in management of hot flashes in survivors of breast cancer: a randomised controlled trial. Lancet 2000;356:2059 - 63.}

. Freeman EW, Rickels K, Yonkers KA, et al. Venlafaxine in the treatment of premenstrual dysphoric disorder. Obstet Gynecol 2001;98:737 - 44.

. Freeman EW, Sondheimer SJ, Rickels K, et al. Efficacy and safety of venlafaxine for premenstrual dysphoric disorder. Obstet Gynecol 2001;97(4 Suppl 1):S9 - S10.

. Effexor® (venlafaxine) package insert. Philadelphia, PA; Wyeth Pharmaceuticals, Inc.; 2005 Nov.

. Bradwejn J, Ahokas A, Stein DJ, et al. Venlafaxine extended-release capsules in panic disorder: flexible-dose, double-blind, placebo-controlled study. Br J Psychiatry. 2005;187:352 - 9.

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