No

Antidepressant, Serotonin/Norepinephrine Reuptake Inhibitor

Treatment of depression; generalized anxiety disorder (GAD)

C

Hypersensitivity to venlafaxine; use of monoamine oxidase inhibitors within 14 days; should not initiate MAOI within 7 days of discontinuing venlafaxine

May cause sustained increase in blood pressure; may cause increase in anxiety, nervousness, insomnia; may cause weight loss (use with caution in patients where weight loss is undesirable). May worsen psychosis in some patients or precipitate a shift to mania or hypomania in patients with bipolar disease. May increase the risks associated with electroconvulsive therapy. Use caution in patients with depression, particularly if suicidal risk may be present. The risks of cognitive or motor impairment, as well as the potential for anticholinergic effects are very low. May cause or exacerbate sexual dysfunction. Abrupt discontinuation or dosage reduction after extended (>6 weeks) therapy may lead to agitation, dysphoria, nervousness, anxiety, and other symptoms. When discontinuing therapy, dosage should be tapered gradually.

greater than or equal to 10%:

Central nervous system: Headache, somnolence, dizziness, insomnia, nervousness

Gastrointestinal: Nausea, xerostomia, constipation, anorexia

Genitourinary: Abnormal ejaculation

Neuromuscular & skeletal: Weakness

Miscellaneous: Diaphoresis

1% to 10%:

Cardiovascular: Hypertension, sinus tachycardia, postural hypotension, vasodilation

Central nervous system: Anxiety, abnormal dreams, agitation, confusion, abnormal thinking, yawning

Dermatologic: Rash, pruritus

Endocrine & metabolic: Decreased libido

Gastrointestinal: Weight loss, vomiting, diarrhea, dyspepsia, flatulence, taste perversion

Genitourinary: Impotence, urinary retention

Neuromuscular & skeletal: Tremor, hypertonia, paresthesia

Ocular: Blurred vision, mydriasis

Otic: Tinnitus

Symptoms of overdose include somnolence and occasionally tachycardia

Most overdoses resolve with only supportive treatment. Use of activated charcoal, inductions of emesis, or gastric lavage should be considered for acute ingestion; forced diuresis, dialysis, and hemoperfusion not effective due to large volume of distribution

CYP2D6, 2E1, and 3A3/4 enzyme substrate; CYP2D6 enzyme inhibitor (weak)

Venlafaxine and its active metabolite o-desmethylvenlafaxine (ODV) are potent inhibitors of neuronal serotonin and norepinephrine reuptake and weak inhibitors of dopamine reuptake; causes beta-receptor down regulation and reduces adenylcyclase coupled beta-adrenergic systems in the brain

Onset of therapeutic effects: >2 weeks

Absorption: Oral: 92% to 100%

Protein binding: Bound to human plasma 27% to 30%; steady-state achieved within 3 days of multiple dose therapy

Metabolism: In the liver by cytochrome P-450 enzyme system to active metabolite, O-desmyethyl-venlafaxine (ODV)

Half-life: 3-7 hours (venlafaxine) and 11-13 hours (ODV)

Time to peak: 1-2 hours

Elimination: Primarily by renal route

Adults: Oral:

Extended-release capsules: 75 mg once daily taken with food; for some new patients, it may be desirable to start at 37.5 mg/day for 4-7 days before increasing to 75 mg once daily; dose may be increased by up to 75 mg/day increments every 4 days as tolerated, up to a maximum of 225 mg/day

Dosing adjustment in renal impairment: Cl_cr 10-70 mL/minute: Decrease dose by 25%; decrease total daily dose by 50% if dialysis patients; dialysis patients should receive dosing after completion of dialysis

Dosing adjustment in moderate hepatic impairment: Reduce total daily dosage by 50%

Alcohol: Additive CNS effect, avoid use

Food: May be taken without regard to food

Blood pressure should be regularly monitored, especially in patients with a high baseline blood pressure

Peak serum level of 163 ng/mL (325 ng/mL of ODV metabolite) obtained after a 150 mg oral dose

Elevations in thyroid, uric acid, glucose, potassium, AST, and cholesterol (S)

No information available to require special precautions

>10% of patients experience significant dry mouth which may contribute to oral discomfort, especially in older patients

Take exactly as directed (do not increase dose or frequency); may take 2-3 weeks to achieve desired results; may cause physical and/or psychological dependence. Take with food. Avoid excessive alcohol, caffeine, and other prescription or OTC medications not approved by prescriber. Maintain adequate hydration (2-3 L/day of fluids unless instructed to restrict fluid intake). You may experience excess drowsiness, lightheadedness, dizziness, or blurred vision (use caution when driving or engaging in tasks requiring alertness until response to drug is known); nausea, vomiting, anorexia, altered taste, dry mouth (small frequent meals, frequent mouth care, chewing gum, or sucking lozenges may help); constipation (increased exercise, fluids, or dietary fruit and fiber may help); diarrhea (buttermilk, yogurt, or boiled milk may help); postural hypotension (use caution when climbing stairs or changing position from lying or sitting to standing); urinary retention (void before taking medication); or sexual dysfunction (reversible). Report persistent CNS effects (eg, insomnia, restlessness, fatigue, anxiety, abnormal thoughts, confusion, personality changes, impaired cognitive function); muscle cramping or tremors; chest pain, palpitations, rapid heartbeat, swelling of extremities, or severe dizziness; unresolved urinary retention; vision changes or eye pain; hearing changes or ringing in ears; skin rash or irritation; or worsening of condition. Do not stop taking this medication abruptly. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to be pregnant. Do not breast-feed.

Causes mean increase in heart rate of 4 beats/minute; tapering to minimize symptoms of discontinuation is recommended when the drug is discontinued; tapering should be over a 2-week period if the patient has received it longer than 6 weeks

Capsule, extended release: 37.5 mg, 75 mg, 150 mg

Tablet: 25 mg, 37.5 mg, 50 mg, 75 mg, 100 mg

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Ellingrod VL and Perry PJ, "Venlafaxine: A Heterocyclic Antidepressant," Am J Hosp Pharm, 1994, 51(24):3033-46.

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Klamerus KJ, Maloney K, Rudolph RL, et al, "Introduction of a Composite Parameter to the Pharmacokinetics of Venlafaxine and Its Active O-desmethyl Metabolite," J Clin Pharmacol, 1992, 32(8):716-24.

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