Botox is probably one of those things you’ve always assumed you’ll think more about in 15 or 20 years. After all, the injectable is largely used by an older demographic to improve the appearance of fine lines and wrinkles. But doctors say the number of young people who are doing preventive Botox (or “preventative Botox”)—i.e., using Botox to stop wrinkles before they start—is growing.

“While five years ago the youngest patients getting Botox were in their late 30s, now we are seeing a lot of women coming in around the time of their 30th birthday to start treating,” Joshua Zeichner, M.D., a New York City-based board-certified dermatologist, tells SELF.

Botox is FDA-approved for people who are 18 and older, Gary Goldenberg, M.D., medical director of the dermatology faculty practice at the Icahn School of Medicine at Mount Sinai, tells SELF, noting that “most of the patients I’ve seen for prevention are in their late 20s or early 30s.”

New York City dermatologist Doris Day, M.D., author of Forget the Facelift, tells SELF that preventative Botox is used to retrain facial muscles and improve facial posture that can cause wrinkles. “By using very precise and discrete placement of a neuromodulator like Botox, I’m affecting specific muscles that are pulling in a direction I don’t want,” she explains. “It allows for opposing muscles to pull in the opposite direction to become stronger over time, allowing for muscles to age more evenly.”