We discuss a case of severe respiratory depression in a child, with ultrarapid CYP2D6 genotype and obstructive sleep apnea syndrome, after taking tramadol for pain relief related to a day-case tonsillectomy.Pain management is challenging after ambulatory tonsillectomy in children and has become more so since the publication of restrictions on the use of codeine for pain relief in children. 1 These restrictions followed reports of severe and fatal respiratory depression in children after the use of codeine for pain relief. [2][3][4][5][6]