What are the common side effects of Duloxetine (Cymbalta)?

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From the Guidelines

Cymbalta (duloxetine) commonly causes several side effects, including nausea, dry mouth, constipation, decreased appetite, fatigue, drowsiness, increased sweating, and dizziness, as reported in the most recent study 1.

Common Side Effects

The most frequently reported side effects of Cymbalta include:

  • Nausea
  • Dry mouth
  • Constipation
  • Decreased appetite
  • Fatigue
  • Drowsiness
  • Increased sweating
  • Dizziness These effects typically occur within the first few weeks of treatment and often improve with time as your body adjusts to the medication.

Less Common Side Effects

Some patients may experience:

  • Insomnia or sleep disturbances
  • Sexual side effects, including decreased libido and difficulty achieving orgasm
  • A slight increase in blood pressure or heart rate in some individuals
  • Blurred vision, tremors, or feelings of nervousness

Serious Side Effects

Rare but potentially serious side effects of Cymbalta include:

  • Suicidal thinking and behavior (through age 24 years)
  • Behavioral activation/agitation
  • Hypomania, mania
  • Sexual dysfunction
  • Seizures
  • Abnormal bleeding
  • Serotonin syndrome
  • Hepatic failure presenting as abdominal pain, hepatomegaly, and elevation of transaminase levels
  • Cholestatic jaundice
  • Severe skin reactions, including erythema multiforme and Stevens-Johnson syndrome If side effects become severe or persistent, it's essential to consult with your healthcare provider rather than stopping the medication abruptly, as sudden discontinuation can lead to withdrawal symptoms including dizziness, nausea, headache, and irritability, as noted in 1.

From the FDA Drug Label

Common possible side effects in people who take duloxetine delayed-release capsules include:

  1. liver damage.
  2. changes in blood pressure and falls. 3 Serotonin Syndrome: 4 abnormal bleeding: 5 severe skin reactions: 6 discontinuation symptoms: 7 manic episodes:
  3. visual problems:
  4. seizures or convulsions
  5. low salt (sodium) levels in the blood. The most common side effects of duloxetine delayed-release capsules include: nausea dry mouth sleepiness fatigue constipation loss of appetite increased sweating dizziness

Common side effects of Cymbalta (duloxetine) include:

  • Nausea
  • Dry mouth
  • Sleepiness
  • Fatigue
  • Constipation
  • Loss of appetite
  • Increased sweating
  • Dizziness 2

From the Research

Common Side Effects of Cymbalta

The common side effects of Cymbalta (duloxetine) are:

  • Nausea
  • Dry mouth
  • Somnolence
  • Constipation
  • Diarrhea
  • Decreased appetite
  • Weight loss
  • Feeling of fatigue
  • Dizziness
  • Hypohidrosis
  • Decreased libido
  • Erectile dysfunction 3
  • Bleeding gums (in rare cases) 3

Side Effects Reported in Clinical Trials

Clinical trials have reported the following side effects with an incidence of ≥ 5.0% and significantly greater than placebo:

  • Nausea
  • Dry mouth
  • Constipation
  • Insomnia
  • Dizziness
  • Fatigue
  • Somnolence
  • Increased sweating
  • Decreased appetite 4
  • Diarrhea 5

Safety Profile

The safety profile of duloxetine is consistent with its labeling, with the most commonly observed significant adverse events being:

  • Nausea
  • Dry mouth
  • Diarrhea
  • Dizziness
  • Constipation
  • Fatigue
  • Decreased appetite 5

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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