Carbenoxolone (CBX) is a glycyrrhetinic acid derivative with a steroid-like structure, similar to substances found in the root of the licorice plant.

[1] Carbenoxolone reversibly inhibits the conversion of inactive cortisone to cortisol by blocking 11β-hydroxysteroid dehydrogenase (11β-HSD).

[4] Carbenoxolone has also been used in topical creams such as Carbosan gel, marketed for treatment of lip sores and mouth ulcers.

[5] This research started from an observation that long-term exposure to glucocorticoids may have negative effects on cognition.

In the research trial investigating this use of carbenoloxone, it was shown that the drug improved verbal fluency in elderly healthy men (aged 55–75).