Hyperactive Delirium Misinterpreted as Breakthrough Pain: A Clinical Illusion

Breakthrough pain (BTP) is the exacerbation of pain in cancer patients and it is highly prevalent. There are other reasons than BTP that can be considered as pain fluctuations in cancer patients. Herein, we present a 46-year-old male with cancer patient who was initially misdiagnosed with BTP. During the BTP treatment process, it was revealed that the patient had hyperactive delirium. This case highlights the importance of including hyperactive delirium in the differential diagnosis of BTP in patients with cancer.