Cymbalta Side Effects

Generic name: duloxetine

Medically reviewed by Drugs.com. Last updated on Sep 21, 2023.

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

Applies to duloxetine: oral capsule delayed release.

Serious side effects of Cymbalta

Along with its needed effects, duloxetine (the active ingredient contained in Cymbalta) 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 duloxetine:

Incidence not known

• Area rash
• blindness
• blistering, peeling, or loosening of the skin
• blurred vision
• change in consciousness
• chest tightness
• chills
• clay-colored stools
• cold sweats
• confusion
• dark urine
• decreased urine output
• decreased vision
• difficulty with swallowing
• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
• eye pain
• fainting
• fast or irregular heartbeat
• general tiredness or weakness
• hives or welts, itching, or skin rash
• hives, itching, puffiness, or swelling of the eyelids or around the eyes, face, lips, or tongue
• increased thirst
• joint or muscle pain
• large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
• light-colored stools
• loss of consciousness
• red skin lesions, often with a purple center
• red, irritated eyes
• redness of the skin
• seizures
• sores, ulcers, or white spots in the mouth or on the lips
• stomach pain
• swelling of the face, ankles, or hands
• tearing
• unpleasant breath odor
• upper right stomach pain
• vomiting of blood
• yellow eyes and skin

Get emergency help immediately if any of the following symptoms of overdose occur while taking duloxetine:

Symptoms of overdose

• Agitation
• diarrhea
• fever
• loss of bladder control
• muscle spasm or jerking of all extremities
• overactive reflexes
• poor coordination
• restlessness
• shivering
• sleepiness or unusual drowsiness
• sudden loss of consciousness
• sweating
• talking or acting with excitement you cannot control
• trembling or shaking
• twitching
• unusual tiredness or weakness
• vomiting

Other side effects of Cymbalta

Some side effects of duloxetine 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

• Body aches or pain
• cough
• difficulty having a bowel movement (stool)
• dry mouth
• ear congestion
• frequent urination
• headache
• lack or loss of strength
• loss of appetite
• loss of voice
• muscle aches
• nausea
• sleepiness or unusual drowsiness
• sneezing
• sore throat
• stuffy or runny nose
• sweating increased
• trouble sleeping
• weight loss

Less common

• Abnormal ejaculation
• abnormal orgasm
• acid or sour stomach
• belching
• burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• change in taste
• change or problem with discharge of semen
• decreased interest in sexual intercourse
• difficulty with moving
• feeling of warmth or redness of the face, neck, arms, and occasionally, upper chest
• heartburn
• inability to have or keep an erection
• indigestion
• longer than usual time to ejaculation of semen
• loose stools
• loss in sexual ability, desire, drive, or performance
• loss of taste
• muscle cramps, pains, or stiffness
• shakiness in the legs, arms, hands, or feet
• stomach discomfort or upset
• sudden sweating
• swollen joints
• trembling or shaking of the hands or feet

For Healthcare Professionals

Applies to duloxetine: oral delayed release capsule.

General

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

Gastrointestinal

Abdominal pain more commonly occurred in pediatric patients.

Constipation occurred most frequently in patients given 60 mg orally 2 times a day (N=225); the side effect occurred in 11% of patients given 60 mg orally once a day, and in 5% of patients given 20 mg orally once a day.

Diarrhea occurred most frequently in patients given 20 mg orally once a day (N=115); the side effect occurred in 7% of patients given 60 mg orally 2 times a day, and in 11% of patients given 60 mg orally once a day.

Dry mouth occurred most frequently in patients in patients with generalized anxiety disorder (GAD) or major depressive disorder (MDD) compared to placebo (N=2995).

Nausea occurred most frequently in patients given 60 mg orally 2 times a day (N=225); the side effect occurred in 22% of patients given 60 mg orally once a day, and in 14% of patients given 20 mg orally once a day.

Vomiting occurred more frequently in patients 13 to 17 years of age with fibromyalgia.^[Ref]

Very common (10% or more): Nausea (up to 30%), constipation (up to 15%), dry mouth (up to 15%), vomiting (up to 15%), abdominal pain (up to 13%), diarrhea (up to 13%)

Common (1% to 10%): Dyspepsia, flatulence, loose stools, oral paresthesia, stomach discomfort, viral gastroenteritis/gastroenteritis

Uncommon (0.1% to 1%): Dysphagia, eructation, gastritis, gastrointestinal bleeding/hemorrhage, halitosis, stomatitis

Rare (0.01% to 0.1%): Gastric ulcer, hematochezia, microscopic colitis

Frequency not reported: Abdominal discomfort, abdominal tenderness, gastrointestinal pain, lower abdominal pain, upper abdominal pain

Postmarketing reports: Pancreatitis, unspecified colitis^[Ref]

Nervous system

Very common (10% or more): Somnolence (up to 21%), headache (up to 18%), dizziness (up to 17%)

Common (1% to 10%): Dysgeusia, facial hypoesthesia, hypoesthesia, lethargy, paresthesia, psychomotor agitation, tremor, vertigo

Uncommon (0.1% to 1%): Akathisia, attention disturbance, dyskinesia, gait disturbance, myoclonus, poor quality sleep, restless legs syndrome, syncope

Rare (0.01% to 0.1%): Convulsion, dysarthria, extrapyramidal disorder, psychomotor restlessness, serotonin syndrome

Very rare (less than 0.01%): Electric shock-like sensation, seizures

Frequency not reported: Hypersomnia, psychomotor hyperactivity, sedation, sensory disturbances

Postmarketing reports: Intracerebral bleeding^[Ref]

Dizziness occurred most frequently in patients given 60 mg orally 2 times a day (N=225); the side effect occurred in 14% of patients given 60 mg orally once a day, and in 6% of patients given 20 mg orally once a day.

Headache more commonly occurred in pediatric patients.

Convulsion and seizures were reported during treatment discontinuation.

Somnolence occurred most frequently in patients given 60 mg orally 2 times a day (N=225); the side effect occurred in 15% of patients given 60 mg orally once a day, and in 7% of patients given 20 mg orally once a day.

Syncope was reported, especially during treatment initiation.^[Ref]

Metabolic

Very common (10% or more): Decreased weight (up to 16%), decreased appetite (up to 16%)

Common (1% to 10%): Anorexia, increased weight

Uncommon (0.1% to 1%): Blood potassium increased, dehydration, hyperglycemia, hyperlipidemia, increased blood cholesterol, thirst

Rare (0.01% to 0.1%): Dyslipidemia, hyponatremia^[Ref]

Decreased appetite occurred more frequently in patients 13 to 17 years of age with fibromyalgia.

Decreased weight of at least 3.5% occurred more frequently in patients 7 to 17 years of age with GAD and/or MDD.

Hyperglycemia was more commonly reported in patients with diabetes.^[Ref]

Respiratory

Very common (10% or more): Nasopharyngitis (up to 14%)

Common (1% to 10%): Cough, oropharyngeal pain, pharyngolaryngeal pain, upper respiratory tract infection, yawning

Uncommon (0.1% to 1%): Epistaxis, throat tightness

Rare (0.01% to 0.1%): Eosinophilic pneumonia, interstitial lung disease^[Ref]

Nasopharyngitis occurred more frequently in patients 13 to 17 years of age with fibromyalgia.^[Ref]

Psychiatric

Very common (10% or more): Insomnia (up to 13%)

Common (1% to 10%): Abnormal dreams, abnormal orgasm, agitation, anorgasmia, anxiety, decreased libido/decreased sex drive, restlessness, sleep disorder, tension

Uncommon (0.1% to 1%): Apathy, bruxism, confusional state, disorientation, irritability, mood swings, nervousness, nightmares, suicidal ideation, suicide attempt

Rare (0.01% to 0.1%): Aggression, anger, completed suicide, hallucinations, mania, suicidal behavior

Frequency not reported: Activation of hypomania, early morning awakening, initial insomnia, intense dreams, loss of libido, middle insomnia, sleep disturbances, terminal insomnia^[Ref]

Aggression and/or anger usually occurred initially or after stopping treatment.

Insomnia occurred most frequently in patients given 60 mg orally 2 times a day (N=225); the side effect occurred in 8% of patients given 60 mg orally once a day, and in 9% of patients given 20 mg orally once a day.^[Ref]

Other

Very common (10% or more): Fatigue (up to 12%)

Common (1% to 10%): Asthenia, chills, falls, feeling jittery, pyrexia, rigors, tinnitus

Uncommon (0.1% to 1%): Ear pain, feeling abnormal, feeling cold/hot, malaise

Frequency not reported: Clinically important drug interactions^[Ref]

Fatigue occurred most frequently in patients given 60 mg orally 2 times a day (N=225); the side effect occurred in 10% of patients given 60 mg orally once a day, and in 2% of patients given 20 mg orally once a day.

Falls were more common in patients 65 years and older.

Tinnitus was reported during treatment discontinuation.^[Ref]

Genitourinary

Common (1% to 10%): Ejaculation delayed, ejaculation disorder, erectile dysfunction, polyuria, urinary frequency

Uncommon (0.1% to 1%): Abnormal urine odor, dysuria, ejaculation dysfunction, ejaculation failure, menopausal symptoms, micturition urgency, nocturia, sexual dysfunction, testicular pain, urinary hesitation, urinary retention

Rare (0.01% to 0.1%): Decreased urine flow, menstrual disorder

Very rare (less than 0.01%): Galactorrhea, gynecological bleeding

Frequency not reported: Genital hypoesthesia, problems getting/keeping an erection^[Ref]

Musculoskeletal

Common (1% to 10%): Muscle cramp, muscle spasms, musculoskeletal pain, myalgia, neck pain

Uncommon (0.1% to 1%): Blood creatine phosphokinase increased, muscle tightness, muscle twitching, musculoskeletal stiffness, trismus

Postmarketing reports: Rhabdomyolysis^[Ref]

Cardiovascular

Common (1% to 10%): Blood pressure increased, flushing/hot flush, palpitations

Uncommon (0.1% to 1%): Atrial fibrillation, chest pain, hypertension, increased diastolic blood pressure, increased systolic blood pressure, myocardial infarction, orthostatic hypertension, peripheral coldness, supraventricular arrhythmia, tachycardia, Takotsubo cardiomyopathy

Rare (0.01% to 0.1%): Hypertensive crisis, supraventricular fibrillation

Frequency not reported: Diastolic hypertension, essential hypertension, labile hypertension, pulse increased, secondary hypertension, systolic hypertension

Postmarketing reports: Cardiac events, ventricular arrhythmias^[Ref]

Orthostatic hypotension was reported, especially during treatment initiation.^[Ref]

Dermatologic

Cutaneous vasculitis was sometimes associated with systemic involvement.^[Ref]

Common (1% to 10%): Hyperhidrosis/increased sweating, pruritus, rash

Uncommon (0.1% to 1%): Cold sweat, contact dermatitis, erythema, night sweats, photosensitivity reaction, urticaria

Rare (0.01% to 0.1%): Ecchymosis

Very rare (less than 0.01%): Cutaneous vasculitis, contusion, Stevens-Johnson syndrome

Frequency not reported: Severe skin reactions, subcutaneous tissue disorder^[Ref]

Ocular

Common (1% to 10%): Blurred vision

Uncommon (0.1% to 1%): Diplopia, dry eye, mydriasis, visual impairment

Rare (0.01% to 0.1%): Glaucoma

Frequency not reported: Angle-closure glaucoma^[Ref]

Immunologic

Common (1% to 10%): Influenza

Uncommon (0.1% to 1%): Laryngitis^[Ref]

Hepatic

Uncommon (0.1% to 1%): Acute liver injury, ALT elevation, alkaline phosphatase elevation, AST elevation, blood bilirubin increased, elevated liver enzymes, GGT increased, hepatitis

Rare (0.01% to 0.1%): Hepatic failure, jaundice

Frequency not reported: Hepatotoxicity, liver failure^[Ref]

Endocrine

Uncommon (0.1% to 1%): Hypothyroidism

Rare (0.01% to 0.1%): Hyperprolactinemia, syndrome of inappropriate antidiuretic hormone secretion (SIADH)^[Ref]

Hypersensitivity

Uncommon (0.1% to 1%): Hypersensitivity disorder

Rare (0.01% to 0.1%): Anaphylactic reaction

Very rare (less than 0.01%): Angioneurotic edema, hypersensitivity^[Ref]

Hematologic

Uncommon (0.1% to 1%): Increased tendency to bruise

Postmarketing reports: Abnormal bleeding events, blood dyscrasias^[Ref]

Renal

Postmarketing reports: Renal dysfunction^[Ref]

Frequently asked questions

• 8 Cymbalta Side Effects: Should I be Concerned?
• How to sleep while taking Cymbalta?
• What helps with Cymbalta withdrawal symptoms?
• Does Cymbalta cause weight gain?
• How long does it take for Cymbalta to work?
• What do Cymbalta brain zaps feel like?
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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.

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