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Atomoxetine Side Effects

In Summary

Commonly reported side effects of atomoxetine include: insomnia, constipation, xerostomia, and decreased appetite. Other side effects include: dysmenorrhea, dermatitis, erectile dysfunction, dizziness, dyspepsia, urinary hesitancy, ejaculatory disorder, ejaculation failure, and diaphoresis. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to atomoxetine: oral capsule

In addition to its needed effects, some unwanted effects may be caused by atomoxetine. In the event that any of these side effects do occur, they may require medical attention.

Severity: Major

You should check with your doctor immediately if any of these side effects occur when taking atomoxetine:

Less common
  • Hives or welts
  • irregular heartbeat
  • itching
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • redness of the skin
  • skin rash
  • Painful, prolonged erection of your penis
Incidence not known
  • Convulsions
  • dark colored urine
  • fainting
  • flu-like symptoms
  • loss of bladder control
  • muscle spasm or jerking of all extremities
  • pelvic pain in male
  • right upper belly pain or tenderness
  • sudden loss of consciousness
  • yellow eyes or skin

Severity: Minor

Some of the side effects that can occur with atomoxetine may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common
  • Acid or sour stomach
  • belching
  • bleeding between periods
  • change in amount of bleeding during periods
  • change in pattern of monthly periods
  • cough
  • decrease in the frequency of urination
  • decrease in urine amount
  • decreased appetite
  • decreased interest in sexual intercourse
  • difficulty having a bowel movement (stool)
  • difficulty in passing urine (dribbling)
  • dizziness
  • dry mouth
  • fever
  • headache
  • heartburn
  • heavy bleeding
  • inability to have or keep an erection
  • indigestion
  • irritability
  • loss in sexual ability, desire, drive, or performance
  • nausea
  • pain or tenderness around the eyes and cheekbones
  • painful urination
  • shortness of breath
  • sleepiness or unusual drowsiness
  • stomach discomfort, upset, cramps, or pain
  • stuffy or runny nose
  • tightness of the chest
  • trouble sleeping
  • unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
  • unusual stopping of menstrual bleeding
  • unusual tiredness or weakness
  • vomiting
Less common
  • Abnormal dreams
  • abnormal orgasm
  • back pain
  • blistering, crusting, irritation, itching, or reddening of the skin
  • bloated or full feeling
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • change in hearing
  • change or problem with discharge of semen
  • chills
  • cold sweats
  • confusion
  • cough
  • cracked, dry, or scaly skin
  • crying
  • decreased weight
  • diarrhea
  • difficulty with moving
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • ear drainage
  • earache or pain in the ear
  • excess air or gas in the stomach or intestines
  • feeling of warmth, redness of the face, neck, arms, and occasionally, upper chest
  • feeling unusually cold
  • frequent urination
  • general feeling of discomfort or illness
  • groin pain
  • increased or sudden sweating
  • joint pain
  • loss of appetite
  • mood swings
  • muscle aches, cramping, pains, or stiffness
  • pain or burning with urination
  • passing gas
  • shivering
  • sinus headache
  • sleep disorder
  • swelling of the skin
  • swollen joints
  • swollen, tender prostate

For Healthcare Professionals

Applies to atomoxetine: oral capsule


Genitourinary side effects reported in adult placebo-controlled trials have included urinary hesitation and/or urinary retention and/or difficulty in micturition (8%), dysmenorrhea (7%), erectile disturbance (7%), ejaculation failure and/or ejaculation disorder (up to 5%), impotence (3%), menstrual disorder (3%), prostatitis (3%), delayed menses, irregular menstruation (2%), and abnormal orgasm (2%). Priapism, hemospermia, male pelvic pain and libido changes have been reported in postmarketing experience.[Ref]


In adult placebo-controlled trials the mean increase in heart rate was reported as 5 beats/minute and the mean increase in blood pressure was reported as 3 mm Hg systolic and 1 mm Hg diastolic.[Ref]

Cardiovascular side effects reported in adult placebo-controlled trials have included palpitations (up to 4%), tachycardia (3%), increased heart rate, and increased blood pressure. Orthostatic hypotension and syncope have been reported in clinical trials. New onset and exacerbation of existing Raynaud's phenomenon as well as QT prolongation have been reported in postmarketing experience.[Ref]


Two cases of severe liver injury (a teenager and an adult) following treatment with atomoxetine for a duration of at least several months have been reported. Both patients recovered. Two additional cases of hepatitis have been reported in children (11 and 12 years of age) following treatment with atomoxetine (30 to 40 mg/day). Symptoms included jaundice, abdominal pain, fatigue, weight loss, arthralgias, diarrhea, vomiting, and elevated liver enzymes. Liver injury completely resolved in both patients following discontinuation of atomoxetine. The number of actual cases of severe liver injury is unknown because of underreporting of postmarketing adverse events.

Atomoxetine should be discontinued in patients who develop jaundice (yellowing of the skin or whites of the eyes) or have laboratory evidence of liver injury. Signs and symptoms of liver problems can include pruritus (itchy skin), jaundice, dark urine, upper right-sided abdominal tenderness, or unexplained flu-like symptoms. Health care professionals are encouraged to report any unexpected adverse events associated with atomoxetine directly to Eli Lilly at 1800-LillyRx or to the FDA MedWatch program at 1800-FDA-1088.[Ref]

Hepatic side effects have included severe hepatic injury.[Ref]


Gastrointestinal side effects reported in adult placebo-controlled trials have included dry mouth (21%), nausea (up to 21%), constipation (up to 10%), abdominal pain (7%), dyspepsia (up to 6%), vomiting (3%), and flatulence (2%). One case of sialolithiasis in association with atomoxetine has been reported and confirmed upon several rechallenges.[Ref]


Respiratory side effects reported in adult placebo-controlled trials have included sinusitis (6%).[Ref]


Musculoskeletal side effects reported in adult placebo-controlled trials have included myalgia (3%).[Ref]

Nervous system

Nervous system side effects reported in adult placebo-controlled trials have included headache (17%), insomnia and/or middle insomnia (16%), dizziness (6%), paraesthesia (4%), somnolence (4%), sinus headache (3%), and tremor (2%). Seizures have been reported in 0.1% of adult patients. There have also been postmarketing reports of hypoesthesia and sensory disturbances.[Ref]


Psychiatric side effects reported in adult placebo-controlled trials have included insomnia (15%), decreased libido (up to 6%), abnormal dreams (4%), and sleep disorders (up to 4%). Mania has been reported rarely. Treatment emergent hostility-related effects have been reported in short-term clinical trials. Patients beginning therapy should be monitored for the appearance or worsening of aggression or hostility.[Ref]

An 11-year-old male with attention deficit disorder developed mania after approximately 3 to 4 weeks of treatment with atomoxetine. The patient returned to his baseline behaviors within 7 days of discontinuing atomoxetine.[Ref]


Dermatologic side effects reported in adult placebo-controlled trials have included increased sweating (4%), dermatitis (2%), and rash (2%).[Ref]


Hypersensitivity side effects have rarely included angioneurotic edema, urticaria, and rash.[Ref]


Ocular side effects have included an increased risk of mydriasis.[Ref]


Other side effects reported in adult placebo-controlled trials have included decreased appetite (up to 11%), fatigue (up to 9%), hot flushes (up to 8%), pyrexia (3%), rigors (3%), unexpected therapeutic response (3%), chills (3%), jittery feeling (2%), and weight loss (2%). Postmarketing side effects reported have included Raynaud's phenomenon and paraesthesia in children and adolescents.[Ref]

Acute treatment studies of up to 9 weeks in duration have reported an average weight loss of 0.4 kg.[Ref]


Renal side effects including urinary hesitation and/or urinary retention (7%), and dysuria (3%) have been reported.


General side effects including lethargy have been reported.[Ref]


1. Raj YP "Atomoxetine-associated hemospermia: a case report." J Clin Psychiatry 69 (2008): 1189

2. "Product Information. Strattera (atomoxetine)." Lilly, Eli and Company, Indianapolis, IN.

3. Lim JR, Faught PR, Chalasani NP, Molleston JP "Severe liver injury after initiating therapy with atomoxetine in two children." J Pediatr 148 (2006): 831-4

4. Jerome L, Gardner D, Kutcher SP "First Case of Sialolithiasis Associated With Atomoxetine." J Clin Psychopharmacol 27 (2007): 111-112

5. Henderson TA, Hartman K "Aggression, mania, and hypomania induction associated with atomoxetine." Pediatrics 114 (2004): 895-6

6. Steinberg S, Chouinard G "A case of mania associated with tomoxetine." Am J Psychiatry 142 (1985): 1517-8

7. Henderson TA "Mania Induction Associated With Atomoxetine." J Clin Psychopharmacol 24 (2004): 567-568

Not all side effects for atomoxetine may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

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.