"Helloooo, ladies!"

That's the come-on intoned by the buff actor in Procter & Gamble Co.'s Old Spice commercials, imploring women to stock up on the men's grooming products for their significant others. It turns out, though, that some are stocking up for themselves.

Young women are embracing Old Spice — long known as the brand dad kept in the medicine cabinet — even as P&G's marketing continues to focus on their male peers. Sarah Olivieri, who started an "Old Spice for Women" Facebook page, said she came to the product for health reasons after searching for a deodorant that wasn't an antiperspirant. Its relatively low price and newer scents also appeal to Old Spice's fans.

"There's a lot of women out there who, for different reasons, like to use Old Spice," said Olivieri, 33, who runs a media company in Rifton, N.Y.

The brand's female inroads represent a small positive for P&G's struggling beauty division, which accounts for about 23 percent of the Cincinnati-based company's revenue. The unit's sales declined 2 percent in the six months that ended Dec. 31 from the year-earlier period.

The whole industry is contending with sluggish growth over the next four years, underscoring the need to find new buyers for its wares. Sales of home-care products are forecast to rise just 2.4 percent a year from 2014 to 2018, according to Euromonitor International.

Cultivating unintended audiences is a delicate process. While pushing a brand's boundaries can fuel growth, the risk is alienating the existing market. The newfound customers also might not want to be courted directly, said Delia Passi, founder of Medelia, a firm in Hollywood, Fla., that advises corporations on selling to women.

"Once you go out with a marketing campaign around it, then it's not cool anymore," she said.

While P&G declined to comment, the company isn't discouraging its new audience. At one point, P&G posted a link to Olivieri's site on its brand page.

Other products have successfully built audiences outside the confines of their brand's target gender. Take Febreze, the odor-neutralizing line of products that's also made by P&G. While the company marketed it toward women for housecleaning, some men spray it on their clothing to delay doing laundry. In Vietnam, where the product is known as Ambi Pur, it's caught on as a deodorizing spray for the helmets worn by riders of the country's ubiquitous motor scooters.

Bag Balm, developed to soothe sore cows' udders, became a popular skin softener for humans and their dogs. Kimberly-Clark's Kleenex was initially seen as a disposable cleaning tissue.

Old Spice's trip to the female market began after an image makeover. Long associated with middle-aged men, Old Spice began a new campaign in 2010 starring actor Isaiah Mustafa as "The Man Your Man Could Smell Like." The first spot, where Mustafa advises that "anything is possible when your man smells like Old Spice and not a lady," has drawn 48 million YouTube views. The campaign also has ad pitches like "Smellcome to Manhood" and "Old Spice Made a Man of My Son," a commercial featuring moms spying on their kids during dates.

Emmi Casulli, 16, of Havertown, Pa., shrugs off the male- oriented marketing. She and her travel soccer team have adopted the brand's Fiji deodorant, which has a softer scent than the classic version.

"It works better than females' deodorant and it smells like a woman's deodorant," Casulli said. "So no one can really tell the difference."

Her teammate, Anna Girod, got the squad hooked on the product after trying her father's stick. She liked it so much, she bought more. Girod, 15, then looped in her friends.

"People make fun of my dad now because the whole soccer team uses it," she said.

For men, using a product that's embraced by women can carry a stigma, said Jill Avery, a senior lecturer at Harvard Business School who has studied the concept of what she calls "gender contamination."

When Porsche's Cayenne SUV became popular with women in 2003, the company "experienced a lot of outcry from its existing users," said Avery, who cowrote a case study on the backlash. "People were unhappy that a different kind of driver would be coming into the family and the brand wouldn't mean what it did in the past."

She also points to traditional men's names such as Ashley. Once parents begin using them for girls, they tend to stop being boys' names, she said.

"A lot of the things we use are gendered," whether that's a brand or a category, Avery said. "If you think about what men are being told from a very young age, it's being masculine is the antithesis of being ­feminine."

If large numbers of women started using Old Spice, or if the company introduced an Old Spice for women or shifted to more unisex marketing, "you might see men leaving the brand because it doesn't convey the masculinity that it did in the past," she said. Bryan McCleary, a P&G spokesman, declined to comment on whether P&G is developing an Old Spice women's line.

Bifurcation can work when the gender distinctions are clear, Avery said. Gillette, acquired by P&G in 2005, unveiled its Gillette for Women Venus razor in 2000, a successful move, Avery said. The brand had previously introduced an even-more-feminine-sounding product in 1915 called Milady Decollete.

Two years ago, Unilever introduced a women's version of Axe body spray, a grooming staple for teenage boys. If the women's version catches on, "Axe is risking some of its male users, because Axe is kind of the pinnacle of masculinity in that category."