Studies of any design exploring the efficacy of CY as an appetite stimulant in all age groups and populations were included. Primary outcomes of studies included were weight gain, appetite stimulation, and/or caloric/nutritional intake increase. The review was completed in accordance with PRISMA standards.
A total of 46 articles across 21 different treatment populations met criteria for the review, including 32 randomized controlled trials, 4 prospective cohort studies, 4 retrospective cohort studies, 4 case reports and 2 case series. Of these, 39 demonstrated that CY resulted in significant weight gain in the sample under study. Studies exploring the use of CY in those with malignant/progressive disease states, such as HIV and cancer, showed minimal to no benefit of the medication. Transient mild to moderate sedation was the most commonly reported side effect. Studies included were heterogeneous in terms of methods as well as study patient demographics, characteristics and concurrent medical conditions. Few studies provided objective measures of appetite change.
CY appears to be a safe, generally well-tolerated medication that has utility in helping facilitate weight gain in patients drawn from a variety of underweight populations. Future prospective randomized controlled studies in low weight patients that include objective measures of appetite and intake are needed to better understand the mechanism by which CY augments weight gain.