Abstract Introduction This study is part of the registrational program for intravenously administered (IV) tramadol in the USA and compared the analgesic benefit and tolerability of two doses of IV tramadol (50 mg and 25 mg) to placebo in adult patients undergoing bunionectomy, an orthopedic surgical model. Methods This was a phase 3, multicenter, double-blind, three-arm, randomized, placebo-controlled, multiple-dose, parallel-group trial to evaluate IV tramadol in the management of postoperative pain following bunionectomy. Eligible patients were randomized (1:1:1 ratio) to IV tramadol 50 mg, 25 mg, or placebo. Primary endpoint was summary of pain intensity differences over 48 h (SPID48). Key secondary endpoints included SPID24, total consumption of rescue analgesia, and patient global assessment of efficacy (PGA). Safety assessments included treatment emergent adverse events (TEAEs), clinical laboratory tests, vital signs, and electrocardiograms (ECGs). Assessment of the dose–response was an important objective of the study. Results The study established a dose response, with IV tramadol 50 mg demonstrating statistically significant benefit (p