Efﬁcacy and safety of ﬂumazenil injection for the reversal
of midazolam sedation after elective outpatient endoscopy
Sang Pyo LEE, In-Kyung SUNG , Jeong Hwan KIM, Sun-Young LEE, Hyung Seok PARK & Chan Sup SHIM
Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Korea
OBJECTIVE: Midazolam sedation during elective
endoscopy is widely performed and ﬂumazenil is
frequently administered after endoscopy to reverse
sedation in clinical practice. This study aimed to
investigate the safety and efﬁcacy of ﬂumazenil injec-
tions after elective endoscopy under midazolam
METHODS: Participants who underwent an upper
endoscopy under midazolam sedation were ran-
domly divided into two groups. In group I, ﬂumaze-
nil was administered i.v. 10 min after the patient’s
transfer to the recovery room, and no antidote was
injected in group II. The time of stay in the recovery
room and adverse events were reviewed through the
nursing records. We asked the patients about their
pain and degree of satisfaction according to a visual
analogue scale (VAS), their memory of the proce-
dure, mental status and the presence of
uncomfortable symptoms on the day of the proce-
dure and the day afterwards.
RESULTS: The length of stay in recovery was signiﬁ-
cantly shorter in group I than in group II. No signiﬁ-
cant differences were found in the number of
patients with pain (VAS ≥1), adverse events and dis-
comfort between the two groups. Additionally, there
were no differences in the patients’ memory of the
procedure, satisfaction with sedation, willingness to
repeat the endoscopy and mental status.
CONCLUSIONS: The time in the recovery room
after ﬂumazenil administration was signiﬁcantly
shortened, and the use of the drug did not increase
the risk of adverse events or discomfort. The use of
ﬂumazenil for reversing midazolam sedation seems
to be safe and effective.
KEY WORDS: benzodiazepines, drug-related side effects and adverse reactions, ﬂumazenil, midazolam.
Midazolam is widely used nowadays for sedation dur-
ing elective endoscopy.
Its sedative effect is medi-
ated by the γ-aminobutyric acid neurotransmitter
Midazolam binds to the benzodiazepine
receptor ligand in the brain and its inhibitory function
results in decreased muscle tone and reduced anxiety.
It has a faster onset of action and a shorter duration
of effect than other benzodiazepines.
Flumazenil, a competitive benzodiazepine antago-
nist, can reverse the sedative and hypnotic effects of
It is well known that ﬂumazenil has
the effect of reversing benzodiazepine-induced seda-
tion and reducing recovery time.
drug is frequently administered after endoscopy
with midazolam sedation in clinical practice.
Correspondence to: In-Kyung SUNG, Department of Internal Medicine,
Digestive Diseases Centre, Konkuk University School of Medicine,
120–121 Neungdong-ro, Gwangjin-gu, Seoul 143-729, Korea.
Conﬂict of interest: None.
Accepted for publication 18 January 2018.
© 2018 Chinese Medical Association Shanghai Branch, Chinese
Society of Gastroenterology, Renji Hospital Afﬁliated to Shanghai
Jiaotong University School of Medicine and John Wiley & Sons
Journal of Digestive Diseases 2018; 19; 93–101 doi: 10.1111/1751-2980.12579