Here’s what you’ll learn when you read this story:

• Minoxidil, the active medical ingredient in products like Rogaine, is a well-known treatment for hair loss, but has poor water solubility and skin permeability.
• A study combines minoxidil with a microneedle that uses stevioside, a naturally occurring sweetener from the Stevia plant.
• Tested on mouse models, scientists found that seviosides increased the absorption of minoxidil, which helped boost the medicine’s overall effectiveness.

Few people like going bald—there’s a reason why hair growth is a multi-billion industry. One of the leading causes of hair loss is androgenetic alopecia, otherwise known as pattern hair loss, which impacts up to 50 percent of both men and women. One of the most widespread medications for baldness, which is the active ingredient in products like Rogaine, is minoxidil (originally developed to treat high blood pressure).

While this treatment has helped many people grow hair, it does come with a few downsides. Standard treatments typically have poor water solubility and skin permeability, so some hair growth experts resort to applying minoxidil with microneedling, a technique that punctures small holes in the top layer of the skin to stimulate growth factors and increase the medication’s absorption.

As described in a 2025 study, scientists from China and Australia have developed a dissolving patch that can perform this microneedling work while also delivering a dose of minoxidil to the scalp, and it’s derived from a somewhat unlikely ingredient: Stevioside (STV), the natural sweetener derived from the Stevia plant. The results of the study were published in the journal Advanced Healthcare Materials.

“Using STV as a novel solubilizing agent, we incorporated minoxidil into a dissolving microneedle patch, which was used to enhance the solubility and bioavailability of minoxidil and overcome the limitations of traditional carrier single-function approaches,” the authors wrote in the study. “This method not only enhances drug penetration into skin but also eliminates other issues associated with traditional topical formulations, such as slow onset of action and/or inaccurate dosing.”

As the authors note, while testosterone doesn’t directly cause baldness, the enzyme 5α-reductase converts testosterone into dihydrotestosterone, which triggers the apoptosis (or death) of keratin-producing cells in the epidermis. Minoxidil, however, suppresses certain enzymes and inhibits androgen receptors, which has the net effect of decreasing the formation and binding of dihydrotestosterone. It also boosts aromatase, which converts testosterone into estradiol—a kind of estrogen that further stimulates hair growth.

To test their new idea, researchers used mouse models with androgenetic alopecia and tested their new patch against standard treatments. In 35 days, scientists saw hair regrowth in 67 percent of the target area, compared to only 25 percent from the control group—a promising start for this Stevia-based hair loss treatment. Of course, mice are one thing, and humans are another.

“While the mouse model results are promising, human hair growth cycles differ, and androgenetic alopecia is influenced by multiple factors,” Lifeng Kang, a co-author of the study from the University of Sydney, told Gizmodo. “Therefore, clinical trials are essential to confirm efficacy and safety in humans.”

Unwanted hair loss isn’t a thing of the past (at least, not yet), but science has it in its crosshairs—no pun intended.