You’ve likely heard of looksmaxxing, the online movement of young men doing whatever they can to maximize their appearance. You may have also heard of “maxxing” in general, recently chosen as Dictionary.com’s word of the year but most often used as a suffix, as in “proteinmaxxing” or “mallmaxxing.”
Or, according to a worrisome new report, “heightmaxxing,” a subset of looksmaxxing and yet another pressure point from the manosphere that’s targeting boys.
“For these young men, the logic is mercilessly efficient: Everything in life is better if you’re tall,” explains the new story in Rolling Stone, in which a reporter recounts his deep dive into heightmaxxing on TikTok — and eventually found teens talking about a troubling solution.
“Eventually, I was watching teenagers discuss something called erda. They posted updates on how much they’d grown and compared notes on side effects. Some showed tape measures against marks on a wall; others labeled videos by how many days they’d been taking it,” reported Jeff Ihaza.
Erda, he soon found out, was short for erdafitinib, “a cancer drug that the boys on my feed believed could make them taller, pointing to reports of unexpected growth in children being treated for cancer. They were willing to endure debilitating symptoms to find out.”
One young man, 17-year-old Zak, had been taking the drug on and off since 15, purchased for $300 a month from an overseas vendor. It’s led to side effects including joint pain, extremely dry skin, and nosebleeds, but after spending time on social media and being made fun of at school for being shorter than girls, said Zak, he stuck with it. “I don’t like other people towering over me,” he said, “and I don’t like having to look up to people.”
Another 17-year-old, James, is also taking erda, despite it causing his fingernails to yellow, ooze pus, and fall off. “Bro, it’s bad,” he said. Still, at five foot five, he was desperate for something to help him grow taller. After starting it in August, he said, “I grew more in two months than I did in one year.”
The drug erdafitinib (brand name Balversa) was first approved in 2019 to treat certain advanced adult bladder cancers, and doctors have used it off-label in clinical trials of children with rare cancers of the central nervous system, according to Rolling Stone. But rough side effects can include diarrhea, pain in the limbs, nausea, and nails separating from their nail beds, as well as excess phosphate in the blood, which can cause mineral deposits in soft tissues.
“It has not been approved to increase height, and its safety and effectiveness have not been established for that purpose or for any use in any children or adolescents,” said a spokesperson for drugmaker Johnson & Johnson in a statement to Rolling Stone, urging patients to consult doctors about treatment and to only use medicines from verified sources under medical supervision.
Still, an erdafitinib study often cited by heightmaxxers, by pediatric endocrinologist Adalbert Raimann and published online in July 2024 in Hormone Research in Paediatrics, described unexpected growth in two children with central nervous system tumors.
Doctors already prescribe growth hormone to help some children grow, although it is an expensive treatment with its own risks, according to Andrew Dauber, a pediatric endocrinologist at Children’s National Hospital in Washington, D.C. Also, he said, there’s a difference between treating a hormone deficiency and intervening because a child is just short. He also said he will not prescribe erda for growth.
“That’s way too dangerous,” he said. “We only know about it at the chemotherapeutic doses.”
James said his parents didn’t let him take growth hormone (though he’s experimented with it), and don’t approve of his taking erda.
But, he said, “There’s this life that I have in mind, and I just want it so badly that I’m not going to let some risk stop me from getting the life I want.” Despite erda’s side effects, he said, which have included vomiting, stomach bleeding that sent him to the hospital, and intense pain that’s forced him to do online school, “I still think it was worth it.”
In fact, the story notes, “James calls his bedroom a lab. He says he sources the drugs through black-market online suppliers.” And in addition to erda and human growth hormone, he says he’s experimented with breast cancer drugs tamoxifen and letrozole, and osteoporosis drug abaloparatide — not to mention compounds that researchers have studied in mice for their effects on bone repair or growth.
Zak, meanwhile, said he believes he needs to keep at it so he can keep improving himself. “I’m trying to maximize every aspect of my body. No matter what I do, I still feel like it’s not enough,” he said, adding that when it comes to girls, “They constantly want something better.”
