Cymbalta is the go-to SNRI for pain. Its three FDA-approved pain indications — diabetic peripheral neuropathy, fibromyalgia, and chronic musculoskeletal pain — give it a formal role in pain management that Effexor simply doesn't have on its label.

Effexor covers more anxiety subtypes on-label: MDD, GAD, social anxiety disorder, and panic disorder. Cymbalta covers MDD and GAD. For social anxiety or panic disorder specifically, Effexor has the broader approved indication set.

Effexor IR has one of the shortest half-lives of any antidepressant (~5 hours), making missed doses and discontinuation particularly uncomfortable. Effexor XR smooths this significantly. Cymbalta's ~12-hour half-life means withdrawal, while real, tends to be more gradual. Both require careful tapering.

Duloxetine is contraindicated in substantial hepatic impairment due to a meaningful hepatotoxicity signal. Venlafaxine does not carry this restriction and is generally the preferred SNRI when liver disease is present. Baseline liver function is worth discussing with any prescriber.

Cymbalta inhibits both CYP1A2 and CYP2D6, giving it a broader drug interaction profile. Effexor is a more moderate CYP2D6 inhibitor. Either way, both warrant a full medication review — especially with other psychiatric drugs, blood thinners, or medications with narrow therapeutic windows.

At lower strengths, Effexor behaves more like an SSRI — the norepinephrine reuptake inhibition is minimal. Cymbalta's norepinephrine effect is more consistent across its strength range, which matters clinically when targeting pain or fatigue symptoms.