#103 Duloxetine (Cymbalta®): Jack of All Trades, Master of None?
CLINICAL QUESTION
How safe and effective is duloxetine for the treatment of chronic painful conditions?
BOTTOM LINE
Compared to placebo, duloxetine appears efficacious in neuropathic pain, improving pain by 50% or more for one in six people. One in 18 people (over placebo) will have to quit due to adverse events.
Reading Tools for Practice Article can earn you MainPro+ Credits
Join NowAlready a CFPCLearn Member? Log in
EVIDENCE
Compared to placebo: meta-analysis1 of three Randomized Controlled Trials (RCTs) with 1,139 diabetic peripheral neuropathy patients over 12 weeks.
- ≥50% improvement in pain: duloxetine 47% vs. placebo 29% (Number Needed to Treat (NNT) 6).
- Mean pain scores improved 2.66 with duloxetine and 1.62 on placebo (on 0–10 scale).
- Adverse events leading to discontinuation: duloxetine 60 mg/day 13.9% vs. placebo 8.3% (Number Needed to Harm (NNH) 18).
- Adverse events included nausea (NNH 9), somnolence (NNH 14), dry mouth (NNH 17), and dizziness (NNH 21).
- Increasing dose no advantage: no difference in response but more adverse events.
- RCT2 of 804 diabetic peripheral neuropathy patients treated with either duloxetine 60 mg/day or pregabalin 300 mg/day for eight weeks.
- ≥50% improvement in pain: duloxetine 40% vs. pregabalin 28% (NNT 9).
- ~12% discontinued treatment due to adverse effects in both groups.
- Trial sponsored by manufacturer of Cymbalta®.
- Previous small trials showed no conclusive difference between duloxetine and amitriptyline3,4 or pregabalin4,5 in neuropathic pain.
- Duloxetine is also efficacious in other chronic painful conditions, including fibromyalgia6 (NNT 8), chemotherapy-induced neuropathic pain (NNT ~9),7 and osteoarthritis of the knee (NNT 6–8).8,9
- For depression, duloxetine has similar efficacy and overall safety to other second generation antidepressants, with no clear advantages compared to other agents.10
- Duloxetine trials are at moderate-to-high risk of bias: industry funding, short duration, high risk of selective outcome reporting, high drop-out rates, multiple outcomes without adjustment and possible selective publication.
Latest Tools for Practice
#353 - Turn Down the Heat! Can non-hormonal drugs improve vasomotor symptoms in menopause? (Free)
Do non-hormonal medications improve menopausal vasomotor symptoms?
#352 Do-It-Yourself Hearing Aids (Free)
Do self-fitted hearing aids improve hearing for adults with mild to moderate-severe hearing loss?
#351 Flaked out? Topical treatment for seborrheic dermatitis (Free)
How effective are topical treatments for adult facial or scalp seborrheic dermatitis?
