Rivastigmine, a cholinesterase inhibitor used for treatment of dementia, decreased the duration of delirium, improved cognitive function and reduced caregiver stress in older patients with ischemic stroke.25 Both olanzapine and haloperidol decreased the severity of delirium in elderly patients admitted to medical wards, and recovery was slightly faster with olanzapine.24 The use of droperidol reduced the length of hospital stay and increased postoperative delirium remission rate in elderly patients with colorectal cancer.28 Here, BCHE is linked to colorectal cancer.