Effectiveness of prednisolone in complex regional pain syndrome treatment: A systematic narrative review.

BACKGROUND: Many patients with complex regional pain syndrome (CRPS) experience refractory pain with severe restrictions in the activities of daily living. Oral prednisolone is commonly used to treat these patients. PURPOSE: To review previous studies assessing the effects of prednisolone in CRPS patients. METHODS AND MATERIALS: Articles published from January 1, 1980 to July 23, 2021 in the PubMed database were searched using the following key phrases: (prednisolone OR corticosteroid OR steroid) AND (complex regional pain syndrome OR reflex sympathetic dystrophy OR shoulder-hand syndrome OR causalgia). Specifically, we included those articles in which oral prednisolone or corticosteroids were used to control the CRPS symptoms. RESULTS: In total, 11 articles were included, comprising 3 randomized trials, 5 single-arm prospective observational studies, and 3 retrospective studies. Nearly all previous studies reported that oral prednisolone can effectively control the CRPS symptoms. Moreover, though 30-100 mg/day of oral prednisolone was initially administered in these studies, 30 mg/day was also found to be effective in controlling the symptoms. Although prednisolone was usually administered for 1-3 months, short-term treatment for 1-2 weeks was also reportedly effective. Furthermore, only 0%-30% of the patients in these studies had minor side effects after prednisolone treatment. CONCLUSIONS: Our review showed that prednisolone may be effective in alleviating the CRPS symptoms. To determine higher levels of evidence, a full systematic review with more highly qualified studies, such as randomized controlled trials, should be conducted in the future.