By Stephanie Stahl

PHILADELPHIA (CBS) — If you thought botox was just for your mom — or grandma — think again. A growing number of younger patients are now getting the injections to hold off the aging process.

The majority of botox users are between ages 40 and 54 — but in 2015 — the academy of plastic surgeons says there were 1.5 million botox injections for patients in their 30’s… And 100,000 for twenty-somethings.

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Every three to four months, 26-year-old Bentley Fitchue makes a regular visit to her dermatologist. Not for something like acne, but for botox injections.

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Bentley used to think botox was for her mother’s generation. But when she began researching online — her opinion changed. She learned celebrities she admired used the treatment as a way to prevent fine lines and wrinkles from deepening as they aged.

“I think any girl my age feels this pressure to sustain the way they look now,” Bentley said, “and anything you can do to prolong those wrinkles is so helpful.”

Dermatologist Terri Martin says since the FDA approved botox in 2002 for cosmetic use its popularity has skyrocketed. In recent years she’s noticed a younger botox patients.

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“When you’re frowning or smiling or laughing the muscles create wrinkles in the skin. When you’re younger those are wrinkles in motion,” Martin said. “But as you get older they become fixed, permanent wrinkles, so the millennials, the younger people, are trying to prevent the wrinkles from becoming wrinkles in motion to wrinkles that are permanent.”

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“I want to start early,” Bentley said. “I want to age softly,”

Just a year into getting the injections — Bentley has seen results.

“My makeup goes on really smooth. If you’ve got an event where you are wearing concealer, you don’t have any creases,” she said. “I have noticed that the more I get them, the less I have to go, so it lasts longer in between treatments.

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Botox results can last from three to nine months. Doctors say the injections are usually cheaper for younger patients because their wrinkles aren’t as deep, so less botox is needed.

Stephanie Stahl