Date of Award


Degree Type

Selective Evidence-Based Medicine Review

Degree Name

Master of Science in Health Sciences - Physician Assistant


Physician Assistant Studies

Department Chair

John Cavenagh, PhD, PA-C


OBJECTIVE: To determine whether or not Orlistat ingested prior to a meal causes an increased appetite response.

STUDY DESIGN: A Review of three randomized controlled trials studies from 2003-2008 that were in the English language.

DATA RESOURCES: Randomized controlled trials comparing the effect of Orlistat on satiety were found using PubMed, OVID, and Cochrane databases.

OUTOMES MEASURED: Outcomes measured in the studies were: sensation of appetite, hunger, fullness, nausea, bloating, heartburn, belching, epigastric burning, and prospective food consumption. Each study measured individual patient responses using a VAS (visual analogue scale). Demarchi et al (2004) used a gastric barostat to measure gastric distention and accommodation to a meal. Both Demarchi (2004) and Goedecke et al (2003) measured plasma CCK levels and Ellrichmann et al (2008) measured gherlin, GLP-1, and PYY in addition to CCK. In addition, Ellrichmann et al (2008) used an ultrasound to determine changes in gallbladder size, and gastric emptying using a C sodium-Octanoate breath test.

RESULTS: Results from both the Demarchi (2004) and Goedecke et al (2003) studies did not demonstrate any significant increase in appetite or inhibition of anorexogenic hormones with Orlistat treatment prior to a test meal. The Ellrichmann et al (2008) results demonstrated decreased gallbladder contractility, increased appetite and food consumption.

CONCLUSIONS: The results of whether Orlistat ingested prior to a meal causes an increased appetite response has not been shown in two of the three studies reviewed. Future tests should include varied fat concentrations in a diet and administered to the same subjects with testing trials in longer duration. Orlistat is still an effective dietary aid in the battle against obesity in today’s society.