This study examines that the use of >200 mg of propofol sedation enables patients to drive home safely after outpatient colonoscopy.

The hospital policy of routine discharge to normal activity 1 hour after propofol mono-sedation for EGD or colonoscopy was approved by the ethics committee of Showa Inan General Hospital in January, 2004 (http://www.sihp.jp). The investigator' s subsequent experience verified the safety of this discharge policy which was reconfirmed in March 2014. Based on these studies, the upper limit of 200 mg was established for those allowed early discharge and driving to home.

This study examines that the use of >200 mg of propofol sedation enables patients to drive home safely 90-120 minutes after outpatient colonoscopy.

Inclusion Criteria:

• subjects who drive home by theirselves after colonoscopy using propofol sedation (>200 mg)

Exclusion Criteria:

• Subjects who received emergency procedures
• less than 20 years old pregnant American Society of Anesthesiologists (ASA) class III or IV, overweight (body weight >100 kg) allergic to the drugs used or its components (soybeans or eggs).

healthy subjects who drive home after colonoscopy using propofol sedation (>200 mg)