OBJECTIVE: To evaluate the efficacy of eutectic mixture of local anesthetics 5% (Emla) in reducing pain associated with lumbar punctures in children. DESIGN: Prospective, double-blind, randomized, placebo-controlled trial. SETTING: University pediatric hospital. PATIENTS: Eleven pediatric oncology patients (mean age 6.6 y, range 4–16) who underwent 31 lumbar punctures. MAIN OUTCOME MEASURES: The analgesic effect was measured by using two methods. The first was a 10-point visual analog scale reported by the patient and the second was an 8-point behavioral pain scale assessed by the nurse who applied the cream. RESULTS: Emla cream was associated with significantly lower pain scores than those with placebo as measured by the patient when the puncture was successful on the first attempt (2.0 +1.6 Emla group, 3.8 +1.9 placebo group; p < 0.05). CONCLUSIONS: The use of Emla cream may reduce pain substantially only in patients who undergo a successful lumbar puncture on the first attempt.