The best medicines can come from unexpected places. Case in point: A new study published today finds that stevia—the natural sugar substitute—can potentially boost common hair loss treatments’ potency.
Scientists in China and Australia developed a dissolving patch that combines a sweetener derived from the stevia plant (Stevia rebaudiana) with topical minoxidil, the active ingredient in popular over-the-counter hair loss drugs like Rogaine. In tests with balding mice, the sweetened patch appeared to enhance minoxidil’s absorption into the skin and boosted its ability to restore hair.
“This work opens exciting possibilities for more effective and user-friendly treatments for hair loss,” study author Lifeng Kang, a senior lecturer at the University of Sydney’s School of Pharmacy, told Gizmodo.
The need for better hair loss treatment
Minoxidil is most commonly used to treat androgenetic alopecia, which is more commonly known as male or female pattern baldness. The condition is primarily caused by having genes that make a person’s hair follicles overly sensitive to androgens (male-related sex hormones). Regular minoxidil use can slow or prevent further balding from androgenetic alopecia, but it has its drawbacks.
The drug doesn’t dissolve easily in liquid nor is it absorbed well into the body when applied topically, which means that it has to be applied a lot to be effective (usually at least once or twice a day). Other commonly added compounds like ethanol and propylene glycol can improve the drug’s skin absorption, but they can also cause side effects, including itching, a rash, and dandruff build-up on your scalp.
A handful of studies suggest that minimally invasive microneedling—causing tiny pricks in the skin—can improve minoxidil’s absorption and even boost hair growth on its own as a result of increasing blood flow to the hair follicles. For the new study, the researchers wondered if it were possible to develop a dissolvable patch that essentially performed microneedling and delivered minoxidil to a person’s scalp at the same time.
According to Kang, other studies had also indicated that natural compounds similar to stevia, including the main sweetener in monk fruit, held specific properties they could use to develop the patch. They hypothesized that stevioside, the primary sweetener in stevia, could act as both the base for their microneedles as well as helping minoxidil dissolve better in water.
Early success
The researchers tested their patch on mice given doses of testosterone to simulate androgenetic alopecia (the hormone doesn’t directly cause pattern baldness in people, but it breaks down into another hormone that does, dihydrotestosterone). They then compared these mice to animals that were given nothing, and mice that were given a standard formulation of minoxidil.
The mice that got the stevia patch experienced clear improvements in hair growth, the researchers found. By day 35, the patch-dosed mice saw hair return in about 67% of the treated area, compared to about 25% of the treated area in mice given standard minoxidil. As hoped, the researchers also found that the patch greatly improved the drug’s absorption into the skin.
The findings, published Wednesday in the journal Advanced Healthcare Materials, are still very preliminary, and more studies will be needed before the patch might make its way to humans, the researchers said.
“While the mouse model results are promising, human hair growth cycles differ, and androgenetic alopecia is influenced by multiple factors,” Kang said. “Therefore, clinical trials are essential to confirm efficacy and safety in humans.”
But given these results, and the fact that stevia is already widely used as a food additive, Kang is hopeful that stevia could prove a safe and easy boost to minoxidil’s effectiveness. He and his team are now looking to explain why stevia boosts the drug’s potency and whether similar compounds could work as well. They are also hoping to run clinical trials in people with pattern baldness.
“The microneedle patch could simplify treatment regimens, reduce dosing frequency, and improve patient adherence,” Kang said.
