Also found in: Dictionary, Wikipedia.
Pharmacologic class: Phenethylamine derivative
Therapeutic class: Antidepressant, anxiolytic
Pregnancy risk category C
Inhibits neuronal serotonin and norepinephrine reuptake and slightly inhibits dopamine reuptake
Capsules (extended-release): 37.5 mg, 75 mg, 150 mg
Tablets: 25 mg, 37.5 mg, 50 mg, 75 mg, 100 mg
Tablets (extended-release): 37.5 mg, 75 mg, 150 mg, 225 mg
Indications and dosages
Adults: In outpatients, 75 mg P.O. daily in two or three divided doses; may increase in increments of 75 mg/day q 4 or more days to a maximum of 225 mg/day; extended-release form can be given as a single daily dose. In hospitalized patients, 75 mg P.O. daily in two or three divided doses; may increase in increments of 75 mg/day q 4 days to a maximum of 375 mg/day given in three divided doses.
➣ Generalized anxiety disorder
Adults: Single dose of 37.5 to 75 mg (extended-release) P.O. daily; may increase in increments of 75 mg/day q 4 days to a maximum of 225 mg/day
➣ Panic disorder
Adults: 37.5 mg (extended-release) P.O. daily for 7 days; increase to 75 mg P.O. daily for 7 days; then increase by 75 mg daily at weekly intervals to a maximum of 225 mg P.O. daily
➣ Social anxiety disorder
Adults: 75 mg (extended-release capsule) P.O. daily as a single dose
• Hepatic or renal impairment
• Premenstrual dysphoric disorder
• Hypersensitivity to drug
• MAO inhibitor use within past 14 days
Use cautiously in:
• cardiovascular disease; hypertension; heart failure, recent myocardial infarction, and other conditions in which increased heart rate poses a danger; hepatic or renal impairment; glaucoma; hyperthyroidism; hyponatremia; syndrome of inappropriate antidiuretic hormone secretion (SIADH)
• history of seizures, neurologic impairment, or drug abuse
• pregnant or breastfeeding patients
• children younger than age 18.
Don't give within 14 days of MAO inhibitors.
CNS: abnormal dreams, anxiety, dizziness, headache, insomnia, nervousness, abnormal thinking, agitation, confusion, depersonalization, drowsiness, emotional lability, worsening depression, twitching, tremor, asthenia, paresthesia, mania, hypomania, suicidal ideation or behavior (especially in child or adolescent)
CV: chest pain, hypertension, palpitations, tachycardia, vasodilation
EENT: visual disturbances, blurred vision, mydriasis, tinnitus, rhinitis
GI: nausea, vomiting, diarrhea, constipation, abdominal pain, dyspepsia, flatulence, dry mouth, anorexia
GU: urinary frequency or retention, sexual dysfunction, abnormal ejaculation, anorgasmia, erectile dysfunction
Metabolic: hyponatremia, SIADH
Skin: bruising, pruritus, rash, diaphoresis, photosensitivity
Other: altered taste, weight loss, chills, yawning
Drug-drug. Cimetidine: increased venlafaxine effects
MAO inhibitors: potentially fatal reactions
Sumatriptan, trazodone: serotonin syndrome (including altered level of consciousness)
Drug-diagnostic tests. Sodium: decreased level
Drug-herbs. Chamomile, hops, kava, skullcap, valerian: increased CNS depression
S-adenosylmethionine (SAM-e), St. John's wort: increased risk of sedative or hypnotic effects
Monitor neurologic status, particularly for seizures, worsening depression, and suicidal ideation.
• Closely monitor vital signs and cardiovascular status. Stay alert for hypertension and tachycardia.
• Monitor nutritional status, hydration, and weight.
• Tell patient taking extended-release capsules to swallow them whole without chewing, breaking, dividing, or dissolving.
Caution patient not to stop therapy abruptly.
Advise patient to promptly report seizures, worsening depression, or suicidal thoughts (especially in child or adolescent).
• Caution patient to avoid driving and other dangerous activities until drug effects are known.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and herbs mentioned above.
Effexor XR(trade name)
Pharmacologic: selective serotonin norepinephrine reuptake inhibitors
Time/action profile (antidepressant action)
|PO||within 2 wk||2–4 wk||unknown|
Adverse Reactions/Side Effects
Central nervous system
- neuroleptic malignant syndrome (life-threatening)
- seizures (life-threatening)
- suicidal thoughts (life-threatening)
- abnormal dreams (most frequent)
- anxiety (most frequent)
- dizziness (most frequent)
- headache (most frequent)
- insomnia (most frequent)
- nervousness (most frequent)
- weakness (most frequent)
- abnormal thinking
- emotional lability
- worsening depression
Ear, Eye, Nose, Throat
- rhinitis (most frequent)
- visual disturbances (most frequent)
- chest pain
- abdominal pain (most frequent)
- altered taste (most frequent)
- anorexia (most frequent)
- constipation (most frequent)
- diarrhea (most frequent)
- dry mouth (most frequent)
- dyspepsia (most frequent)
- nausea (most frequent)
- vomiting (most frequent)
- weight loss (most frequent)
- sexual dysfunction (most frequent)
- urinary frequency
- urinary retention
- ecchymoses (most frequent)
- skin rash
- paresthesia (most frequent)
- serotonin syndrome (life-threatening)
- chills (most frequent)
Drug-Drug interactionConcurrent use with MAO inhibitors may result in serious, potentially fatal reactions (wait at least 2 wk after stopping MAO inhibitor before initiating venlafaxine; wait at least 1 wk after stopping venlafaxine before starting MAO inhibitors).Concurrent use with MAO-inhibitor like drugs, such as linezolid or methylene blue may ↑ risk of serotonin syndrome; concurrent use contraindicated; do not start therapy in patients receiving linezolid or methylene blue ; if linezolid or methylene blue need to be started in a patient receiving venlafaxine, immediately discontinue venlafaxine and monitor for signs/symptoms of serotonin syndrome for 2 wk or until 24 hr after last dose of linezolid or methylene blue, whichever comes first (may resume venlafaxine therapy 24 hr after last dose of linezolid or methylene blue)Concurrent use with alcohol or other CNS depressants, including sedatives/hypnotics, antihistamines, and opioid analgesics in depressed patients is not recommended.Drugs that affect serotonergic neurotransmitter systems, including tricyclic antidepressants, SNRIs, fentanyl, buspirone, tramadol and triptans ↑ risk of serotonin syndromeLithium may have ↑ serotonergic effects with venlafaxine; use cautiously in patients receiving venlafaxine.↑ blood levels and may ↑ effects of desipramine and haloperidol.Cimetidine may ↑ the effects of venlafaxine (may be more pronounced in geriatric patients, those with hepatic or renal impairment, or those with pre-existing hypertension).Ketoconazole may ↑ the effects of venlafaxine.↑ risk of bleeding with NSAIDS, aspirin, clopidogrel, or warfarin.Concomitant use of kava-kava, valerian, chamomile, or hops can ↑ CNS depression.↑ risk of serotinergic side effects including serotonin syndrome with St. John’s wort and SAMe.
Route/DosageMajor Depressive Disorder
Hepatic ImpairmentOral (Adults) ↓ daily dose by 50% in patients with mild-to-moderate hepatic impairment.
Renal ImpairmentOral (Adults) CCr 10–70 mL/min—↓ daily dose by 25–50%; Hemodialysis—↓ daily dose by 50%.
Availability (generic available)
- Assess mental status and mood changes. Inform health care professional if patient demonstrates significant increase in anxiety, nervousness, or insomnia.
- Assess suicidal tendencies, especially in early therapy. Restrict amount of drug available to patient. Risk may be increased in children, adolescents, and adults ≤24 yr.
- Monitor BP before and periodically during therapy. Sustained hypertension may be dose-related; decrease dose or discontinue therapy if this occurs.
- Monitor appetite and nutritional intake. Weigh weekly. Report continued weight loss. Adjust diet as tolerated to support nutritional status.
- Assess for serotonin syndrome (mental changes [agitation, hallucinations, coma], autonomic instability [tachycardia, labile BP, hyperthermia], neuromuscular aberrations [hyper-reflexia, incoordination], and/or GI symptoms [nausea, vomiting, diarrhea]), especially in patients taking other serotonergic drugs (SSRIs, SNRIs, triptans).
- Lab Test Considerations: Monitor CBC with differential and platelet count periodically during therapy. May cause anemia, leukocytosis, leukopenia, thrombocytopenia, basophilia, and eosinophilia.
- May cause an ↑ in serum alkaline phosphatase, bilirubin, AST, ALT, BUN, and creatinine.
- May also cause ↑ serum cholesterol.
- May cause electrolyte abnormalities (hyperglycemia or hypoglycemia, hyperkalemia or hypokalemia, hyperuricemia, hyperphosphatemia or hypophosphatemia, and hyponatremia).
- May cause false-positive immunoassay screening tests for phencyclidine (PCP) and amphetamine.
Potential Nursing DiagnosesIneffective coping (Indications)
Risk for injury (Side Effects)
- Do not confuse Effexor with Effexor XR.
- Oral: Administer venlafaxine with food.
- Extended-release capsules should be swallowed whole; do not crush, break, or chew.
- Extended-release capsules may be opened and contents sprinkled on a spoonful of applesauce. Take immediately and follow with a glass of water. Do not store mixture for later use.
- Instruct patient to take venlafaxine as directed at the same time each day. Take missed doses as soon as possible unless almost time for next dose. Do not double doses or discontinue abruptly. Patients taking venlafaxine for >6 wk should have dose gradually decreased before discontinuation.
- Advise patient, family, and caregivers to look for suicidality, especially during early therapy or dose changes. Notify health care professional immediately if thoughts about suicide or dying, attempts to commit suicide; new or worse depression or anxiety; agitation or restlessness; panic attacks; insomnia; new or worse irritability; aggressiveness; acting on dangerous impulses, mania, or other changes in mood or behavior or if symptoms of serotonin syndrome occur.
- May cause drowsiness or dizziness. Caution patient to avoid driving or other activities requiring alertness until response to the drug is known.
- Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and consult health care professional before taking any new medications. Caution patient to avoid taking alcohol or other CNS-depressant drugs during therapy.
- Instruct patient to notify health care professional if signs of allergy (rash, hives) occur.
- Instruct female patients to inform health care professional if pregnancy is planned or suspected or if breast feeding.
- Emphasize the importance of follow-up exams to monitor progress. Encourage patient participation in psychotherapy.
- Increased sense of well-being.
- Renewed interest in surroundings. Need for therapy should be periodically reassessed. Therapy is usually continued for several months.
- Decreased anxiety.
Effexor®Venlafaxine Psychiatry A mood-enhancing SSRI used for major depression, general anxiety disorder Contraindications Should not be combined with MAOIs. See Depression, Major depression, Monoamine oxidase inhibitor.
Patient discussion about Effexor
Q. Effexor Hi! I am new to the forum. I was diagnosed eight months ago with effexor - induced mania and now have been diagnosed as Bipolar II, rapid cycling, with mixed states. I have a 30 year old history of treatment-resistant depression. No mania prior to the effexor. I also self-treat the depression with one hour of vigorous exercise daily, sunlight, healthy diet, regular sleep, and no stimulants or depressants including coffee and alcohol. I take omega 3, magnesium malate, calcium, zinc, selenium, and super b-complex supplements as well.