Most Frequent Side Effects of Cymbalta
Cymbalta (duloxetine), an SNRI antidepressant, commonly causes nausea (up to 23% of patients), dry mouth (11-15%), drowsiness (10%), fatigue (9-10%), constipation (9-10%), and dizziness (8-9%). These often improve after the first week or two as the body adjusts.[1][2]
Side Effects by Body System
- Gastrointestinal: Nausea tops the list, followed by decreased appetite (7-8%), vomiting (4-5%), and diarrhea (6%).[1]
- Nervous system: Headache (14%), somnolence (10%), and insomnia (10%) are routine.[2]
- Other common ones: Sweating (6-8%), blurred vision (4%), and sexual dysfunction like decreased libido (3-6%) or erectile issues (4%).[1][3]
About 10-20% of users stop due to these, especially early in treatment.[2]
Serious but Less Common Risks
Watch for serotonin syndrome (confusion, rapid heart rate, fever), suicidal thoughts (especially in young adults), liver damage (yellowing skin), or low sodium (headache, weakness). Seek immediate help for severe allergic reactions like rash or swelling.[1][4] Orthostatic hypotension can cause falls, particularly in older patients.[2]
How Long Do Side Effects Last?
Most peak in the first 1-2 weeks and fade within a month. Tapering off slowly prevents withdrawal symptoms like irritability or electric shock sensations.[3][4]
Managing Common Side Effects
Take with food to cut nausea. Stay hydrated for dry mouth. Avoid driving if drowsy. Doctors often start at 30mg to minimize issues before raising to 60mg.[1][2]
Who Experiences Them Most?
Higher rates in women, elderly, or those on higher doses (60-120mg). Pre-existing conditions like anxiety amplify insomnia or sweating.[2][3]
[1]: FDA Cymbalta Label
[2]: Drugs.com - Cymbalta Side Effects
[3]: Mayo Clinic - Duloxetine
[4]: WebMD - Cymbalta