A transdermal scopolamine patch is an effective medication for relieving motion sickness, treating nausea and vomiting from chemotherapy and decreasing withdrawal side-effects from wearing off opioids. A 14-year-old boy with chronic granulomatous disease and severe infection was admitted to the hospital because of left shoulder aspergillus' infection and pain. The patient required high dose opioid to control the shoulder pain. A unilateral fixed and dilated pupil was noted. We assumed this to be related to the advancing central nervous system aspergillosis. After extensive neurological 'work up', we realized that the anisocoria was related to the transdermal scopolamine patch that we had prescribed for weaning off the opioid.