Does Duloxetine Reduce Sub-Acute Pain After Knee Arthroplasty?

Does Duloxetine Reduce Sub-Acute Pain After Knee Arthroplasty?

We are investigating the impact of duloxetine ("Cymbalta"), a serotonin and norepinephrine reuptake inhibitor, on pain after total knee arthroplasty (TKA). Specifically, the investigators will determine whether duloxetine, 60 mg daily for 2 weeks, reduces pain scores 2 weeks after TKA.

Inclusion Criteria:

• Patients with osteoarthritis scheduled for primary tricompartmental total knee arthroplasty with a participating surgeon
• Age 25 to 75 years
• Planned use of regional anesthesia
• Ability to follow study protocol
• English speaking (primary outcome obtained via telephone call and secondary outcomes include questionnaires validated in English only)
• Patients planning on being discharged home or to a rehabilitation center that has agreed to participate

Exclusion Criteria:

• Concurrent use of duloxetine or other SNRIs, MAOIs, Tricyclic antidepressants, triptans (sumatriptan, rizatriptan, naratriptan, zolmitriptan, eletriptan, almotriptan, frovatriptan), lithium, buspirone, St. John's Wort
• Hepatic insufficiency
• Renal insufficiency
• Patients younger than 25 years old and older than 75
• Patients intending to receive general anesthesia
• Allergy or intolerance to one of the study medications
• Patients with an ASA of IV
• Chronic gabapentin/pregabalin use (regular use for longer than 3 months)
• Chronic opioid use (taking opioids for longer than 3 months)
• Patients with major prior ipsilateral open knee surgery