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Effexor Side Effects

Generic name: venlafaxine

Medically reviewed by Drugs.com. Last updated on Sep 25, 2023.

Note: This document contains side effect information about venlafaxine. Some dosage forms listed on this page may not apply to the brand name Effexor.

Applies to venlafaxine: oral capsule extended release, oral tablet, oral tablet extended release.

Warning

Oral route (Capsule, Extended Release)

Antidepressants increased the risk of suicidal thoughts and behavior in pediatric and young adult patients in short-term studies. Closely monitor all antidepressant-treated patients for clinical worsening, and emergence of suicidal thoughts and behaviors. Venlafaxine hydrochloride is not approved for use in pediatric patients.

Oral route (Tablet; Tablet, Extended Release)

Antidepressants increased the risk compared to placebo of suicidal thinking and behavior (suicidality) in children, adolescents, and young adults in short-term studies of Major Depressive Disorder (MDD) and other psychiatric disorders. Anyone considering the use of venlafaxine hydrochloride or any other antidepressant in a child, adolescent, or young adult must balance this risk with the clinical need. Short-term studies did not show an increase in the risk of suicidality with antidepressants compared to placebo in adults beyond age 24; there was a reduction in risk with antidepressants compared to placebo in adults aged 65 and older. Depression and certain other psychiatric disorders are themselves associated with increases in the risk of suicide. Patients of all ages who are started on antidepressant therapy should be monitored appropriately and observed closely for clinical worsening, suicidality, or unusual changes in behavior. Families and caregivers should be advised of the need for close observation and communication with the prescriber. Venlafaxine is not approved for use in pediatric patients

Serious side effects of Effexor

Along with its needed effects, venlafaxine (the active ingredient contained in Effexor) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking venlafaxine:

More common

Less common

Rare

Incidence not known

Other side effects of Effexor

Some side effects of venlafaxine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common

Incidence not known

For Healthcare Professionals

Applies to venlafaxine: oral capsule extended release, oral tablet, oral tablet extended release.

General

The most commonly reported side effects were nausea, headache, somnolence, and dizziness.[Ref]

Gastrointestinal

Very common (10% or more): Nausea (up to 58%), dry mouth (up to 22%), constipation (up to 15%)

Common (1% to 10%): Abdominal pain, diarrhea, dyspepsia, eructation, flatulence, vomiting

Uncommon (0.1% to 1%): Circumoral paresthesia, colitis, dysphagia, esophagitis, gastritis, gastroenteritis, gastrointestinal hemorrhage, gastrointestinal ulcer, gingivitis, glossitis, hemorrhoids, melena, mouth ulceration, oral moniliasis, rectal hemorrhage, stomatitis, tongue edema

Rare (less than 0.1%): Abdominal distention, buccoglossal syndrome, cheilitis, cholecystitis, cholelithiasis, duodenitis, esophageal spasm, gastroesophageal reflux disease, gum hemorrhage, hematemesis, hyperchlorhydria, ileitis, increased salivation, intestinal obstruction, pancreatitis, parotitis, periodontitis, proctitis, salivary gland enlargement, soft stools, tongue discoloration[Ref]

Nervous system

Very common (10% or more): Headache (up to 38%), somnolence (up to 26.1%), dizziness (up to 23.9%), tremor (up to 10.2%)

Common (1% to 10%): Akathisia, amnesia, dysgeusia, hypertonia, hypesthesia, increased muscle tone, migraine, paresthesia, sedation, taste perversion, vertigo

Uncommon (0.1% to 1%): Abnormal coordination, abnormal speech, ataxia, balance disorder, central nervous system (CNS) stimulation, dyskinesia, hyperesthesia, hyperkinesia, hypotonia, incoordination, myoclonus, neuralgia, neuropathy, parosmia, seizure, syncope, stupor, taste loss, visual field defect

Rare (0.1% to 0.01%): Abnormal gait, akinesia, aphasia, bradykinesia, cerebral ischemia, cerebrovascular accident, convulsion, dementia, dystonia, facial paralysis, Guillain-Barre Syndrome, hypokinesia, loss of consciousness, neuritis, neuroleptic malignant syndrome (NMS), nystagmus, paresis, reflexes decreased, reflexes increased, serotonin syndrome, torticollis

Very rare (less than 0.01%): Extrapyramidal reactions, tardive dyskinesia

Frequency not reported: Impaired coordination, sensory disturbance

Postmarketing reports: Coordination abnormal, impaired balance, involuntary movements, NMS-like reactions, shock-like electrical sensations[Ref]

Psychiatric

Very common (10% or more): Insomnia (up to 24%), nervousness (up to 21.3%), abnormal orgasm (up to 12.5%), anxiety (up to 11.2%)

Common (1% to 10%): Abnormal dreams, abnormal thinking, agitation, anorgasmia, confusion, depersonalization, depression, libido decreased, orgasm disturbance, orgasmic dysfunction

Uncommon (0.1% to 1%): Apathy, bruxism, derealization, emotional lability, euphoria, hallucination, hostility, hypomania, libido increased, mania, manic reaction, psychosis, suicidal ideation, suicide attempt, withdrawal syndrome

Rare (less than 0.1%): Alcohol abuse, delirium, delusions, homicidal ideation, hysteria, impulse control difficulties, paranoid reaction, psychotic depression, psychomotor restlessness

Frequency not reported: Aggression, delayed orgasm, increased dreaming, intense dreams, nightmares, other sleep disorders, self-harm, sleep disturbances, suicidal behaviors, vivid dreams, withdrawal symptoms

Postmarketing reports: Catatonia, confusional state, panic, paranoia, psychotic disorder[Ref]

Dermatologic

Very common (10% or more): Sweating (up to 19.3%), night sweats (up to 11.4%)

Common (1% to 10%): Ecchymosis, hyperhidrosis, pruritus, rash

Uncommon (0.1% to 1%): Acne, alopecia, brittle nails, contact dermatitis, dry skin, eczema, face edema, maculopapular rash, photosensitivity reaction, psoriasis, skin hypertrophy, urticaria

Rare (less than 0.1%): Cellulitis, erythema multiforme, erythema nodosum, exfoliative dermatitis, furunculosis, granuloma, hair discoloration, hirsutism, leukoderma, lichenoid dermatitis, miliaria, mucocutaneous hemorrhage, petechial rash, pruritic rash, purpura, pustular rash, seborrhea, skin atrophy, skin discoloration, skin striae, Stevens-Johnson syndrome, sweating decreased, toxic epidermal necrolysis, vesiculobullous rash[Ref]

Metabolic

Very common (10% or more): Anorexia (up to 20%)

Common (1% to 10%): Blood cholesterol increased, decreased appetite, increased appetite, weight gain, weight loss

Uncommon (0.1% to 1%): Dehydration, hyperglycemia, hyperlipemia, hyperlipidemia, hypokalemia, hyponatremia, increased alkaline phosphatase, thirst

Rare (less than 0.1%): Alcohol intolerance, diabetes mellitus, gout, hemochromatosis, hypercholesteremia, hyperkalemia, hyperphosphatemia, hyperuricemia, hypocholesteremia, hypoglycemia, hypophosphatemia, hypoproteinemia

Frequency not reported: Height changes, loss of appetite, weight changes

Postmarketing reports: Lactate dehydrogenase (LDH) increased[Ref]

Other

Very common (10% or more): Asthenia (up to 19%)

Common (1% to 10%): Accidental injury, chills, fatigue, fever, tinnitus, trauma

Uncommon (0.1% to 1%): Hyperacusis, intentional injury, malaise, otitis media

Rare (less than 0.1%): Abortion, deafness, energy increased, feeling drunk, healing abnormal, labyrinthitis, menopause, motion sickness, otitis externa

Frequency not reported: Discontinuation syndrome, pain

Postmarketing reports: Congenital anomalies[Ref]

Genitourinary

Very common (10% or more): Abnormal ejaculation (up to 16%)

Common (1% to 10%): Albuminuria, enlarged prostate, erectile dysfunction, impotence, metrorrhagia, pollakiuria, prostatic disorder, prostatitis, urinary frequency, urinary hesitation, urinary retention, urination impaired, vaginitis

Uncommon (0.1% to 1%): Amenorrhea, bladder pain, breast pain, cystitis, dysuria, hematuria, leukorrhea, menorrhagia, nocturia, pelvic pain, polyuria, prostate irritability, pyuria, urinary incontinence, urinary urgency, vaginal hemorrhage

Rare (less than 0.1%): Balanitis, breast discharge, breast engorgement, breast enlargement, calcium crystalluria, cervicitis, endometriosis, galactorrhea, hypercalcinuria, hypomenorrhea, lactation (female), mastitis, menstrual disorders associated with increased bleeding or increased irregular bleeding, ovarian cyst, orchitis, prolonged erection, salpingitis, urolithiasis, uterine hemorrhage, uterine spasm, vaginal dryness

Frequency not reported: Delayed ejaculation, dysmenorrhea

Postmarketing reports: Proteinuria[Ref]

Cardiovascular

Common (1% to 10%): Chest pain, edema, hot flashes/hot flush, hypertension/increased blood pressure, palpitation, postural hypotension, substernal chest pain, tachycardia, vasodilation

Uncommon (0.1% to 1%): Angina pectoris, arrhythmia, bradycardia, cold feet, cold hands, extrasystoles, hypotension, orthostatic hypotension, peripheral vascular disorder, thrombophlebitis

Rare (less than 0.1%): Aortic aneurysm, arteritis, bigeminy, bundle branch block, capillary fragility, cardiovascular disorder (mitral valve and circulatory disturbance), coronary artery disease, congestive heart failure, cyanosis, ECG QT prolonged, first-degree atrioventricular block, heart arrest, hematoma, myocardial infarct, pallor, sinus arrhythmia, torsade de pointes, ventricular fibrillation, ventricular tachycardia

Postmarketing reports: Atrial fibrillation, deep vein thrombophlebitis, ECG abnormalities, stress cardiomyopathy, supraventricular tachycardia, Takotsubo cardiomyopathy, ventricular extrasystole[Ref]

Respiratory

Common (1% to 10%): Bronchitis, cough increased, dyspnea, pharyngitis, sinusitis, yawn/yawning

Uncommon (0.1% to 1%): Asthma, chest congestion, epistaxis, hyperventilation, laryngismus, laryngitis, pneumonia, voice alteration

Rare (less than 0.1%): Atelectasis, hemoptysis, hypoventilation, hypoxia, interstitial lung disease, larynx edema, pleurisy, pulmonary embolus, pulmonary eosinophilia, sleep apnea

Frequency not reported: Rhinitis, upper respiratory infection, upper respiratory tract infection[Ref]

Ocular

Common (1% to 10%): Abnormality of accommodation, abnormal vision, blurred vision, mydriasis

Uncommon (0.1% to 1%): Cataract, conjunctivitis, corneal lesion, diplopia, dry eyes, eye pain, photophobia

Rare (less than 0.1%): Angle-closure glaucoma, blepharitis, chromatopsia, conjunctival edema, decreased pupillary reflex, exophthalmos, eye hemorrhage, keratitis, miosis, papilledema, retinal hemorrhage, scleritis, subconjunctival hemorrhage, uveitis

Frequency not reported: Difficulty focusing eyes[Ref]

Musculoskeletal

Common (1% to 10%): Neck pain, trismus, twitching

Uncommon (0.1% to 1%): arthritis, arthrosis, bone pain, bone spurs, bursitis, leg cramps, myasthenia, neck rigidity, tenosynovitis

Rare (less than 0.1%): Muscle cramp, muscle spasms, musculoskeletal stiffness, myopathy, osteoporosis, osteosclerosis, pathological fracture, plantar fasciitis, rhabdomyolysis, rheumatoid arthritis, tendon rupture

Frequency not reported: Arthralgia, back pain, myalgia

Postmarketing reports: Bone fracture, creatine phosphokinase (CPK) increased[Ref]

Immunologic

Common (1% to 10%): Flu syndrome, infection

Uncommon (0.1% to 1%): Moniliasis

Rare (less than 0.1%): Appendicitis, bacteremia[Ref]

Hematologic

Uncommon (0.1% to 1%): Anemia, leukocytosis, leukopenia, lymphadenopathy, mucous membrane bleeding, mucosal hemorrhage, thrombocythemia, thrombocytopenia

Rare (less than 0.1%): Agranulocytosis, aplastic anemia, basophilia, blood dyscrasias, eosinophilia, lymphocytosis, neutropenia, pancytopenia, prolonged bleeding time

Postmarketing reports: INR increased, prolonged partial thromboplastin time, prothrombin time increased[Ref]

Hepatic

Uncommon (0.1% to 1%): Abnormal liver function tests, ALT increased, AST increased

Rare (less than 0.1%): Biliary pain, bilirubinemia, cholecystitis, cholelithiasis, hepatitis, jaundice, liver tenderness

Postmarketing reports: Fatty liver, GGT elevation, hepatic reactions, liver damage, liver failure, liver necrosis[Ref]

Renal

Uncommon (0.1% to 1%): Kidney calculus, kidney pain

Rare (less than 0.1%): Anuria, blood urea nitrogen (BUN) increased, creatinine increased, glycosuria, kidney function abnormal, oliguria, pyelonephritis, uremia

Postmarketing reports: Renal failure[Ref]

Hypersensitivity

Uncommon (0.1% to 1%): Angioedema

Rare (less than 0.1%): Anaphylactic reaction, anaphylaxis

Frequency not reported: Hypersensitivity[Ref]

Endocrine

Rare (0.1% to 0.01%): Goiter, gynecomastia (male), hyperthyroidism, hypothyroidism, inappropriate antidiuretic hormone secretion (SIADH)/syndrome of inappropriate antidiuretic hormone secretion, thyroid nodule, thyroiditis

Very rare (less than 0.01%): Blood prolactin increased[Ref]

Oncologic

Rare (less than 0.1%): Carcinoma, fibrocystic breast, multiple myeloma[Ref]

Frequently asked questions

References

1. Product Information. Effexor (venlafaxine). Wyeth-Ayerst Laboratories. 2001;PROD.

2. Product Information. Effexor XR (venlafaxine). Wyeth-Ayerst Laboratories. 2002.

3. Cerner Multum, Inc. UK Summary of Product Characteristics.

4. Cerner Multum, Inc. Australian Product Information.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.