Cyproheptadine, an antihistamine and antiserotonergic agent, is an appetite stimulant
that is efficacious in promoting weight gain in children and adults with poor appetite.
Despite numerous studies showing that cyproheptadine achieved positive outcomes, studies
documenting its effectiveness on appetite are limited. This study evaluated the efficacy
and tolerability of cyproheptadine in adults with poor appetite in South Korea.
Patients aged 19 to 64 years with poor appetite were randomly assigned to receive
either cyproheptadine or placebo for 8 weeks. The primary end point was the difference
between the groups in change in appetite, as measured by the Korean version of the
Edmonton Symptom Assessment System from the beginning to the end of the study period.
The secondary end points included effects on weight, anthropometrics, body composition,
Simplified Nutritional Appetite Questionnaire–measured appetite, and toxicities. A
total of 375 patients were randomly assigned to the two groups (189 cyproheptadine,
The cyproheptadine group experienced a mean (SD) change in appetite score of –2.42
(0.12) compared with –2.03 (0.13) in the placebo arm, representing a statistically
significant appetite gain in the cyproheptadine group (difference, +0.38 [0.18]; 95%
CI, –0.73 to –0.04; P = 0.0307). Patients in the cyproheptadine group experienced significant increases
in weight and body mass index. The most common adverse event was somnolence, as predicted.
Cyproheptadine was well tolerated, with one serious adverse event (colitis) which
was classified as a moderate adverse effect unlikely to be related to the study drug.
We present the largest randomized, double-blind, placebo-controlled clinical trial
of cyproheptadine versus placebo in healthy adults with poor appetite using the lowest
effective dosage of cyproheptadine. Cyproheptadine is a safe treatment option in patients
with poor appetite. Our findings provide important information for the use of cyproheptadine
to ameliorate poor appetite in adults. Further randomized studies focused on the effect
of cyproheptadine in older populations are needed.