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Serzone Side Effects

Generic Name: nefazodone

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

For the Consumer

Applies to nefazodone: oral tablet

Along with its needed effects, nefazodone (the active ingredient contained in Serzone) 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 as soon as possible if any of the following side effects occur while taking nefazodone:

More common
  • Blurred vision or other changes in vision
  • clumsiness or unsteadiness
  • lightheadedness or fainting
  • ringing in the ears
  • skin rash or itching
Less common
  • Bladder pain
  • bloody or cloudy
  • cough or hoarseness
  • diarrhea
  • excessive muscle tone
  • eye pain
  • feeling dizzy
  • frequent urge to urinate
  • itching of the vagina or genital area
  • muscle stiffness
  • muscle tension or tightness
  • nausea
  • pain during sexual intercourse
  • painful, burning, or difficult urination
  • shortness of breath, tightness in chest, or wheezing
  • stomach pain
  • thick, white vaginal discharge with no odor or with a mild odor
  • troubled breathing
  • Asthma
  • bleeding from the rectum
  • bloody or black, tarry stools
  • change in sexual desire or performance
  • chest pain
  • double vision
  • dryness of eye
  • ear pain
  • fainting
  • fast heartbeat
  • fever, chills, or sore throat
  • hallucinations (seeing, hearing, or feeling things that are not there)
  • hives
  • increased sense of hearing
  • increased sensitivity to sun
  • irritation or soreness of mouth
  • joint or muscle pain or stiffness
  • kidney stones
  • large pupils of eyes
  • lower back, side, or stomach pain
  • menstrual changes
  • mood or mental changes
  • nerve pain or twitching
  • pelvic pain
  • problems in speaking
  • problems with urination
  • prolonged, painful, inappropriate penile erection
  • red or irritated eyes
  • sensitivity of eyes to light
  • swelling of face
  • swollen glands
  • talking, feeling, and acting with excitement and activity you cannot control
  • unusual bleeding or bruising
  • unusual feeling of well-being
  • unusual tiredness or weakness
  • vomiting of blood or material that looks like coffee grounds
Incidence not known
  • Blistering, peeling, or loosening of skin
  • light-colored stools
  • confusion
  • dark urine
  • decreased urine output
  • fever
  • increased thirst
  • itching
  • lack of appetite
  • large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • muscle pain or cramps
  • muscle spasm or jerking of all extremities
  • muscle stiffness
  • pain, warmth, or burning in fingers, toes, and legs
  • red skin lesions, often with a purple center
  • sore throat
  • sudden loss of consciousness
  • sweating
  • vomiting

Some side effects of nefazodone 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
  • Abnormal dreams
  • agitation
  • confusion
  • constipation
  • diarrhea
  • dizziness
  • drowsiness
  • dryness of mouth
  • flushing or feeling of warmth
  • headache
  • heartburn
  • increased appetite
  • increased cough
  • memory problems
  • nausea
  • swelling of arms or legs
  • tingling, burning, or prickly sensations
  • tremor
  • trouble in sleeping
  • vomiting
Less common or rare
  • Breast pain
  • generalized slowing of mental and physical activity
  • increased thirst
  • loss of strength or energy
  • muscle weakness
Incidence not known
  • Unexpected or excess milk flow from breasts
  • swelling of the breasts or breast soreness in males

For Healthcare Professionals

Applies to nefazodone: oral tablet


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

Nervous system

Very common (10% or more): Headache (up to 36%), somnolence (up to 28%), dizziness (up to 22%), lightheadedness (up to 10%)
Common (1% to 10%): Ataxia, decreased concentration, hypertonia, incoordination, memory impairment, paresthesia, taste perversion, tremor
Uncommon (0.1% to 1%): Abnormal gait, decreased attention, dysarthria, hangover effect, myoclonus, neuralgia, twitching, vertigo
Rare (less than 0.1%): Cerebrovascular accident, hyperesthesia, hyperkinesia, hypotonia, neuroleptic malignant syndrome, taste loss
Frequency not reported: Central nervous system stimulation, hypesthesia, migraine
Postmarketing reports: Convulsions, grand mal seizures, serotonin syndrome[Ref]


Very common (10% or more): Dry mouth (up to 25%), nausea (up to 23%), constipation (up to 17%)
Common (1% to 10%): Diarrhea, dyspepsia, gastroenteritis, vomiting
Uncommon (0.1% to 1%): Colitis, enlarged abdomen, eructation, esophagitis, gastritis, gingivitis, halitosis, mouth ulceration, peptic ulcer, periodontal abscess, rectal hemorrhage, stomatitis
Rare (less than 0.1%): Dysphagia, gastrointestinal hemorrhage, glossitis, increased salivation, oral moniliasis, ulcerative colitis
Frequency not reported: Abdominal pain, flatulence, tooth disorder[Ref]


Very common (10% or more): Asthenia (up to 11%)
Common (1% to 10%): Chills, fever, tinnitus
Uncommon (0.1% to 1%): Ear pain, hernia, malaise
Rare (less than 0.1%): Deafness
Frequency not reported: Accidental injury, pain[Ref]


Very common (10% or more): Insomnia (up to 11%)
Common (1% to 10%): Abnormal dreams, agitation, confusion, decreased libido, psychomotor retardation
Uncommon (0.1% to 1%): Abnormal thinking, apathy, depersonalization, derealization, euphoria, hallucinations, hostility, increased libido, paranoid reaction, suicidal thoughts, suicide, suicide attempt
Rare (less than 0.1%): Anorgasmia
Frequency not reported: Anxiety, depression, dysphoria, emotional lability[Ref]


In clinical trials, scotomata and visual trails did not occur in patients given doses below 300 mg/day; however, these events were reported at doses below 300 mg/day in postmarketing experience.[Ref]

Very common (10% or more): Abnormal vision (up to 10%)
Common (1% to 10%): Blurred vision, eye pain, scotoma, visual field defect, visual trails
Uncommon (0.1% to 1%): Abnormality of accommodation, conjunctivitis, diplopia, dry eye, hyperacusis, keratoconjunctivitis, mydriasis, photophobia
Rare (less than 0.1%): Angle-closure glaucoma, night blindness, ptosis[Ref]


Common (1% to 10%): Feeling warm, flushing, hypotension, peripheral edema, postural hypotension, sinus bradycardia, vasodilatation
Uncommon (0.1% to 1%): Angina pectoris, hypertension, syncope, tachycardia, ventricular extrasystoles
Rare (less than 0.1%): Atrioventricular (AV) block, congestive heart failure, hemorrhage, pallor, varicose veins
Frequency not reported: Chest pain, edema, palpitation[Ref]


Common (1% to 10%): Breast pain, impotence, urinary frequency, urinary retention, urinary tract infection, vaginitis
Uncommon (0.1% to 1%): Abnormal ejaculation, amenorrhea, breast enlargement, hematuria, menorrhagia, metrorrhagia, nocturia, pelvic pain, polyuria, urinary incontinence, urinary urgency, vaginal hemorrhage
Rare (less than 0.1%): Enlarged uterine fibroids, oliguria, uterine hemorrhage
Frequency not reported: Dysmenorrhea, dysuria
Postmarketing reports: Galactorrhea, priapism[Ref]


Common (1% to 10%): Bronchitis, dyspnea, increased cough, pharyngitis
Uncommon (0.1% to 1%): Asthma, epistaxis, hiccup, laryngitis, pneumonia, voice alteration
Rare (less than 0.1%): Hyperventilation, yawn
Frequency not reported: Rhinitis, sinusitis[Ref]


Common (1% to 10%): Pruritus, rash
Uncommon (0.1% to 1%): Acne, alopecia, dry skin, ecchymosis, eczema, face edema, maculopapular rash, photosensitivity reaction, urticaria, vesiculobullous rash
Rare (less than 0.1%): Cellulitis
Frequency not reported: Sweating
Postmarketing reports: Stevens-Johnson syndrome[Ref]


Common (1% to 10%): Increased appetite, thirst
Uncommon (0.1% to 1%): Dehydration, gout, increased lactic dehydrogenase, weight loss
Rare (less than 0.1%): Hypercholesteremia, hypoglycemia
Frequency not reported: Anorexia, weight gain
Postmarketing reports: Hyponatremia[Ref]


Rhabdomyolysis occurred in patients receiving this drug with lovastatin or simvastatin.[Ref]

Common (1% to 10%): Arthralgia, neck rigidity
Uncommon (0.1% to 1%): Arthritis, bursitis, muscle stiffness, tenosynovitis
Rare (less than 0.1%): Tendinous contracture
Frequency not reported: Back pain, cramp, myalgia, neck pain
Postmarketing reports: Rhabdomyolysis[Ref]


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


Common (1% to 10%): Decreased hematocrit
Uncommon (0.1 to 1%): Anemia, leukopenia, lymphadenopathy
Postmarketing reports: Thrombocytopenia[Ref]


Uncommon (0.1% to 1%): Abnormal liver function tests, increased ALT, increased AST
Rare (less than 0.1%): Hepatitis
Postmarketing reports: Liver failure (in some cases leading to liver transplantation and/or death), liver necrosis[Ref]


Uncommon (0.1% to 1%): Cystitis, kidney calculus[Ref]


Uncommon (0.1% to 1%): Allergic reaction
Postmarketing reports: Anaphylactic reactions, angioedema[Ref]


Postmarketing reports: Gynecomastia, increased prolactin[Ref]


1. "Product Information. Serzone (nefazodone)." Bristol-Myers Squibb, Princeton, NJ.

Some side effects of Serzone may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.