Pentacyclic triterpenoids are a class of naturally occurring compounds found in a variety of plants, including Centella asiatica (gotu kola), olive, and some medicinal herbs. Recent research has explored their potential use in supporting hair growth and addressing hair loss or thinning. The most studied pentacyclic triterpenoid in this context is asiaticoside, a component of Centella asiatica. Preclinical studies, including in vitro cell culture experiments and animal models, have suggested that pentacyclic triterpenoids may promote proliferation of dermal papilla cells, enhance extracellular matrix production, and improve microcirculation in the scalp, all of which could theoretically support hair follicle health and hair growth.

However, direct clinical evidence in humans is limited. A few small studies and some patent literature suggest topical preparations containing pentacyclic triterpenoids may have beneficial effects on hair density and growth, but these studies often lack rigorous controls, involve small sample sizes, or are unpublished. No large, placebo-controlled clinical trials have definitively established efficacy. Thus, while there is a plausible scientific rationale and some preliminary preclinical evidence, the overall quality and quantity of human data is low. The use of pentacyclic triterpenoids for hair loss is therefore supported by early-stage scientific evidence, with more robust clinical trials needed to confirm their effectiveness.