Refractory pruritus caused by sintilimab and its clinical management: A case report

Several immune related adverse events (irAEs) were reported with the wide application of immune checkpoint inhibitors (ICIs) in tumors. ICI-related skin reactions are the most common, which are manifested as maculopapules, rash, pruritus, vitiligo, psoriasis, and lichenoid rash.Among them, the incidence of pruritus is second only to maculopapule/rash, but both often co-exist. The severity of pruritus is mostly mild to moderate and can be relieved after symptomatic treatment with antihistamines. Symptoms are slightly relieved after conventional treatment in patients with severe pruritus, but it easily recurs and eventually develops into refractory pruritus.The patient's quality of life may be affected and may also be life-threatening.We report a case of a patient with postoperative recurrence of gallbladder neuroendocrine carcinoma,who developed refractory pruritus after sintilimab use, which was relieved after naloxone infusion after unsuccessful conventional drug therapy. By analyzing the treatment plan of this typical case of immune-related refractory pruritus after using sintilimab, this report discusses how clinical pharmacists can provide individualized treatment of patients by using their expertise and clinicians' cooperation and complementation in treating clinically difficult cases. This case report may be used as a reference in treating patients with refractory pruritus after the clinical use of sintilimab.