STUDY OBJECTIVE: Acute musculoskeletal pain in emergency department (ED) patients is frequently severe and challenging to treat with medications alone. The purpose of this study was to determine the feasibility, acceptability, and effectiveness of adding ED acupuncture to treat acute episodes of musculoskeletal pain in the neck, back, and extremities. METHODS: In this pragmatic 2-stage adaptive open-label randomized clinical trial, Stage 1 identified whether auricular acupuncture (AA; based on the battlefield acupuncture protocol) or peripheral acupuncture (PA; needles in head, neck, and extremities only), when added to usual care was more feasible, acceptable, and efficacious in the ED. Stage 2 assessed effectiveness of the selected acupuncture intervention(s) on pain reduction compared to usual care only (UC). Licensed acupuncturists delivered AA and PA. They saw and evaluated but did not deliver acupuncture to the UC group as an attention control. All participants received UC from blinded ED providers. Primary outcome was 1-hour change in 11-point pain numeric rating scale. RESULTS: Stage 1 interim analysis found both acupuncture styles similar, so Stage 2 continued all 3 treatment arms. Among 236 participants randomized, demographics and baseline pain were comparable across groups. When compared to UC alone, reduction in pain was 1.6 (95% confidence interval [CI]: 0.7 to 2.6) points greater for AA+UC and 1.2 (95% CI: 0.3 to 2.1) points greater for PA+UC patients. Participants in both treatment arms reported high satisfaction with acupuncture. CONCLUSION: ED acupuncture is feasible and acceptable and can reduce acute musculoskeletal pain better than UC alone.