Giving an analgesic to patients with right lower quadrant (RLQ) pain causes greater alteration of abdominal signs predictive of appendicitis than placebo. A randomized double-blinded controlled trial of 68 patients who received either tramadol or placebo. Absence or presence of seven abdominal signs (tenderness on light and deep palpation, tenderness in the RLQ and elsewhere, rebound, cough, and percussion tenderness) and pain (100 mm Visual Analog Scale [VAS]) at 0 and 30 minutes were recorded. The predictive value of each physical finding (PF) was measured using an 11-point PF score weighted by likelihood ratios. There was significant reduction in mean VAS of 14.2 mm (95% CI 5.6 to 22.8) in analgesic group versus 6.5 mm (95% CI 1.6 to 11.4) in placebo group. The analgesic group had less normalization of signs as measured by the PF score in all patients [32 of 154 (20.8%) versus 40 of 121 (33.1 %) (P = .031)] and in those with proven appendicitis [4 of 33 (12.1%) versus 10/22 (45.5%) (P = .014)]. Parenteral use of tramadol in emergency department patients with RLQ pain resulted in significant levels of pain reduction without concurrent normalisation of abdominal examination findings indicative of acute appendicitis.