Class: Serotonin/Norepinephrine Reuptake Inhibitor
Dosage Forms. Capsule, Extended Release: 37.5 mg, 75 mg, 150 mg; Tablet: 25 mg, 37.5 mg, 50 mg, 75 mg, 100 mg; Tablet, Extended Release: 37.5 mg, 75 mg 150 mg, 225 mg
Common FDA Label Indication, Dosing, and Titration.
1. Generalized anxiety disorder: Extended release, 37.5-75 mg po daily; may titrate to 225 mg/d
2. Depression: Immediate release, 75 mg po daily in 2-3 divided doses, may titrate to 225 mg/d; Extended release, 37.5-75 mg po daily; may titrate to 225 mg/d
3. Panic disorder: Extended release, 37.5 mg po daily × 7 d, then 75 mg po daily, may titrate to 225 mg/d
1. Obsessive-compulsive disorder: Immediate release, 25 mg po tid, may titrate to 300 mg/d
2. Premenstrual dysphoric disorder: Immediate release, 25 mg po bid, may titrate to 200 mg/d
MOA. Potent reuptake inhibitor of serotonin and norepinephrine but lacks effects on muscarinic, α-adrenergic, or histamine receptors.
Drug Characteristics: Venlafaxine
Medication Safety Issues: Venlafaxine
Drug Interactions: Venlafaxine
Adverse Reactions: Venlafaxine
Efficacy Monitoring Parameters. Improvement in depression, anxiety, and panic symptoms.
Toxicity Monitoring Parameters. Worsening of depression, suicidality, or unusual changes in behavior, especially at the initiation of therapy or with dosage increases or decreases; signs/symptoms of abnormal bleeding; signs/symptoms of abnormal bleeding; monitor BP, LFT, serum cholesterol levels, in case of severe impairment at baseline and periodically during therapy; signs/symptoms of hyponatremia, especially in patients on concomitant diuretics, volume-depleted patients, and elderly.
Key Patient Counseling Points. Take venlafaxine with food, but avoid alcohol. Extended-release capsule and tablets should be swallowed whole. Contents of extended-release capsules may be sprinkled on food and swallowed without chewing, followed by water. Symptomatic improvement may not be evident for a few weeks. Do not discontinue drug abruptly, as this may precipitate withdrawal symptoms such as dysphoric mood, irritability, and agitation. Avoid activities requiring mental alertness, may cause dizziness or somnolence.
Clinical Pearls. May convert to extended-release capsules or tablets based on nearest equivalent dose (mg/d) of stable immediate-release dose.