Irinotecan-induced dysarthria has been reported in the literature, but the underlying mechanism of this neurotoxicity remains unclear. Here, we present a 35-year-old female with metastatic colon cancer who experienced dysarthria during irinotecan infusion. Her symptoms were decreased and eventually eliminated with subsequent increases in infusion time. When the patient returned to original 90 min infusion time, symptoms were significantly reduced in both severity and duration as compared to the first infusion. We suggest infusion time as a potential intervention for patients experiencing dysarthria, and we review the existing literature, explore treatment options, and discuss proposed mechanisms surrounding this unusual adverse drug reaction.