The objective of this study was to determine if judicious dosing of morphine sulfate can provide pain relief without changing important physical examination findings in patients with acute appendicitis. We conducted a prospective, randomized, double-blind crossover design. Patients scheduled for appendectomy were randomized to two groups. Group A received 0.075 mg/kg intravenous morphine sulfate and 30 minutes later received placebo. The sequence of medication was reversed in group B. Patients were examined by a surgical resident and an EM attending before and after receiving medication. Six explicit physical examination findings were documented as absent, indeterminate, or present. Physicians were also asked if they felt overall examination findings had changed after medication. Patient's visual analog scale (VAS) was recorded before each medication and at study completion. Thirty-four patients were enrolled and full data were available for 22 patients. Neither morphine nor placebo caused a significant change in individual examination findings. Three patients in both groups were judged to have a change in their examination after medication. The median change in VAS was 20 mm after morphine and 0 mm after placebo (P =.01). In this pilot study, patients with clinical signs of appendicitis were treated with morphine and had significant improvement of their pain without changes in their physical examination.