From the Guidelines
Cymbalta (duloxetine) commonly causes several notable side effects, including nausea, dry mouth, constipation, decreased appetite, fatigue, drowsiness, increased sweating, and dizziness, as reported in a study published in the Mayo Clinic Proceedings 1. The most frequent side effects of Cymbalta include:
- Nausea
- Dry mouth
- Constipation
- Decreased appetite
- Fatigue
- Drowsiness
- Increased sweating
- Dizziness Many patients also experience sleep disturbances such as insomnia or unusual dreams. Sexual dysfunction, including decreased libido and difficulty achieving orgasm, affects a significant number of users. Some people report headaches, blurred vision, and increased blood pressure. When starting Cymbalta, these side effects are often most pronounced during the first few weeks of treatment and may diminish over time as the body adjusts to the medication. More serious but less common side effects include serotonin syndrome (characterized by agitation, hallucinations, rapid heart rate, and high fever), liver problems, abnormal bleeding, low sodium levels, and severe skin reactions, as noted in a study published in Ophthalmology 1. Abrupt discontinuation can cause withdrawal symptoms including dizziness, irritability, headaches, and "brain zaps" (electric shock-like sensations), so the medication should always be tapered gradually under medical supervision. These side effects occur because Cymbalta works by increasing serotonin and norepinephrine levels in the brain, which affects multiple body systems beyond just mood regulation. It is essential to monitor patients for these side effects and adjust the treatment plan accordingly to minimize the risk of adverse effects and optimize the quality of life for patients taking Cymbalta.
From the FDA Drug Label
Duloxetine delayed-release capsules may cause serious side effects, including:
- liver damage.
- changes in blood pressure and falls. 3 Serotonin Syndrome: 4 abnormal bleeding: 5 severe skin reactions: 6 discontinuation symptoms: 7 manic episodes:
- visual problems:
- seizures or convulsions
- 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
The main side effects of Cymbalta (duloxetine) include:
- Serious side effects:
- Liver damage
- Changes in blood pressure and falls
- Serotonin Syndrome
- Abnormal bleeding
- Severe skin reactions
- Discontinuation symptoms
- Manic episodes
- Visual problems
- Seizures or convulsions
- Low salt (sodium) levels in the blood
- Common side effects:
- Nausea
- Dry mouth
- Sleepiness
- Fatigue
- Constipation
- Loss of appetite
- Increased sweating
- Dizziness 2
From the Research
Main Cymbalta Side Effects
There are no research papers provided that directly discuss the main side effects of Cymbalta (duloxetine). However, some studies mention duloxetine as part of their research:
- A study published in 2019 3 mentions duloxetine as one of the antidepressant medications used in the treatment of major depressive disorder, but it does not provide information on its side effects.
- No other studies provided mention Cymbalta or duloxetine side effects.
Related Information
While the studies do not provide information on Cymbalta side effects, they do discuss the efficacy and safety of various antidepressant medications, including selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), in the treatment of major depressive disorder:
- A 2004 study 4 compared the effectiveness of fluoxetine, cognitive-behavioral therapy (CBT), and their combination in the treatment of adolescents with major depressive disorder.
- A 2014 study 5 conducted a multiple-treatments meta-analysis to assess the efficacy, acceptability, and safety of various interventions, including medicinal and cognitive-behavioral therapy, in children and adolescents with major depressive disorder.
- A 2005 study 6 discussed the comparative efficacy of CBT, fluoxetine, and their combination in depressed adolescents.
- A 2015 study 7 examined the prophylactic efficacy of four commonly used SSRIs, including fluoxetine, escitalopram, sertraline, and paroxetine, in major depressive disorder, as well as the effect of concomitant CBT.