Medical experts are warning of a dangerous new social media trend known as “heightmaxxing,” amid reports that teenagers are taking black-market cancer medications in an effort to grow taller.
Adolescents, primarily teenage boys, are reportedly turning to erdafitinib â often referred to online as “ERDA” or “Erta” â a targeted prescription drug approved to treat advanced bladder cancer.
Teenagers are reportedly experimenting with the prescription medication after encountering online discussions suggesting it could increase height.
“Itâs extremely concerning that teenagers are experimenting with powerful cancer medications in an attempt to grow taller,” Dr. Stephanie Widmer, a New York City-based emergency medicine physician and Fox News medical contributor, told Fox News Digital.
“These drugs were developed to treat serious medical conditions, not to enhance physical appearance, and taking them without a legitimate medical indication or physician supervision can have devastating consequences.”
The drug maker, Johnson & Johnson, pushed back against the practice in a statement to Rolling Stone, emphasizing that the medication has never been approved to stimulate height growth and that its safety and effectiveness have not been established for any pediatric or adolescent use.
Medical research has documented unexpected growth spurts in children receiving erdafitinib for brain tumors. A 2024 study published in Hormone Research in Paediatrics described accelerated growth in two pediatric patients, while a separate case report documented a teenager who grew more than 5 inches during treatment but developed serious skeletal complications.
Callout:
Physicians caution that these spurts do not equal healthy skeletal growth. Dr. Jessica Gray, a family physician in Lubbock, Texas, warned that forced, rapid growth can trigger dangerous structural problems, including premature growth plate damage and bone fractures.
The drug works by blocking specific cellular signaling pathways involved in cancer cell growth, Widmer shared during an appearance on Fox News’ “America’s Newsroom.”
Those same pathways also play a role in bone development, which may help explain why some pediatric patients experienced unexpected growth during treatment.
Widmer noted that height is overwhelmingly governed by genetics, and biological shortcuts do not exist. Once growth plates close near the end of puberty, medications cannot reopen them, meaning older adolescents taking the compound are incurring catastrophic health hazards without any chance of gaining height, she said.
“One of the biggest concerns is that these medications can cause serious side effects, including potentially permanent vision damage, elevated phosphate levels and other metabolic abnormalities,” Widmer said.
“Weâre talking about adolescents whose bodies are still developing, and exposing them to these risks for a cosmetic goal is particularly troubling.”
Other warning signs and side effects linked to the medication include skeletal pain â especially in the hips or knees â as well as mouth sores, loose nails and skin disorders.
The trend has also raised concerns about the influence of social media on teenagers’ decisions about their health. Widmer noted that online discussions about physical appearance and self-improvement can expose young men to potentially unsafe practices that lack medical evidence.
“Parents need to understand that this goes beyond teenagers being insecure about their height,” the doctor said.
“Weâre talking about young people potentially obtaining prescription cancer medications and experimenting with them outside of medical supervision. If a child has concerns about their growth, that conversation belongs in a pediatricianâs office, not on an internet forum.”
Doctors advise parents to watch for symptoms such as unusual joint pain or unexplained physical changes, and to speak with their children if they suspect they are using medications obtained online.
Teenagers concerned about their height or growth should consult a pediatrician before considering any medication.
“We should be encouraging teenagers to prioritize their health, not teaching them to gamble with it,” Widmer said. “No amount of additional height is worth risking permanent damage to your vision or other serious and potentially unknown medical complications.”
