Orlistat mouth rinse effectively lowers total and fat calorie intake in obese individuals

In this double-blind, balanced order, crossover study, the participants (n = 10, body mass index 25-30 kg/m2) were randomized to consume placebo or orlistat (24 mg/mL) prior to a high-fat meal. Following placebo delivery, participants were separated into low-fat and high-fat consumers based on the number of calories ingested from fat.

The key findings of this study were:

The orlistat mouth rinse reduced total and fat calories taken during the high-fat meal in high-fat consumers but had no effect on low-fat consumers (P 0.05).

Orlistat reduces long-chain fatty acid (LCFA) absorption by blocking the lipases that break down lipids. Orlistat mouth rinse reduced fat intake in high-fat consumers, indicating that orlistat prevented LCFA detection from the high-fat test meal. Orlistat delivered orally is expected to reduce the risk of oil incontinence and also enhance weight loss in people who prefer fat based food.

Reference: 

Primeaux, S. D., Dubin, R., & Greenway, F. L. (2023). Orlistat mouth rinse: Using the tongue to deliver antiobesity medication in a double‐blind randomized crossover pilot trial. In Diabetes, Obesity and Metabolism. Wiley. https://doi.org/10.1111/dom.15101