Teenagers Turning to Cancer Drugs to Increase Height: The Reality of "Height Maxing"

Chemotherapy for "a Few More Centimeters"? The Pressure of "Height Supremacy" on Young People and the Dangers of Social Media

"If I were just a little taller, I'd be more confident."

This thought is leading some to try cancer treatment drugs on themselves.

On November 12, 2026, the English Daily Mail reported cases of teenagers obtaining erdafitinib, a drug used to treat bladder cancer and other conditions, for the purpose of increasing their height. Online, this drug is referred to by abbreviations like "ERDA."

The act of trying to maximize height is called "height maxxing." Interest in height itself is not unusual. However, the story changes significantly when drugs requiring professional management are self-administered as a means of improving appearance.

What needs to be emphasized in this issue is that the "possibility of growing taller" is not the same as "growing healthily and safely."

The "acceleration of growth" during cancer treatment becomes an attractive effect online

Erdafitinib is a molecular targeted drug that suppresses the function of the FGFR receptor, which is involved in cell proliferation. In the United States, it is used for adult patients with advanced urothelial cancer with specific FGFR3 gene abnormalities, provided certain conditions like treatment history are met.

It is not approved as a drug for increasing height.

Nevertheless, there is actual medical research that has drawn attention. A paper published online in 2024 reported unexpected growth acceleration in two children treated with this drug for central nervous system tumors.

There is cartilage tissue called the "growth plate" where bone length increases. FGFR3 is one of the receptors involved in regulating this growth. Researchers considered the possibility that the drug's impact on this function could explain the growth acceleration.

However, this was not a clinical trial for height increase in healthy young people. The subjects were children who had growth issues due to tumors or past treatments.

Moreover, the reported changes were not limited to height. Abnormal expansion of the growth plate and changes in bone images were also confirmed.

If you only take a part of the research, it becomes an attractive story of "cancer drugs made someone taller." However, looking at the entire paper, it is clear that careful consideration is needed to understand what is happening to the growing bones.

Experiences of "growing taller" alone cannot determine the drug's effects

The Daily Mail, citing an interview with Rolling Stone, introduced the experiences of 17-year-olds who claimed to have used the drug.

While height increase was discussed, symptoms such as severe joint pain, nosebleeds, nail discoloration, and pus were also reported. There was even testimony of saving money for medical expenses.

These are reports conveyed by the media based on personal claims and should be distinguished from medically verified data on the drug's effects.

During adolescence, height increases even without drugs. There are individual differences in growth periods, and measurement conditions can also affect the numbers. For products obtained online, there remains the issue of whether the contents were as labeled.

Therefore, just because height increased after taking the drug, one cannot conclude that "it's thanks to this drug" based solely on the temporal relationship.

Whether short-term growth leads to an increase in final adult height is another question. Furthermore, if disabilities in bones or eyes occur during the process, the length gained cannot simply be evaluated as a success.

Eye Disorders, Phosphorus Metabolism Abnormalities, and Skeletal Effects

The concern is not a vague "it's scary because it's a cancer drug" narrative.

U.S. prescription information includes risks such as eye disorders related to the retina and calcification of soft tissues due to hyperphosphatemia. Management during treatment requires examinations by ophthalmologists and blood tests.

It is also clearly stated that safety and efficacy in children have not been established. In pediatric patients, disorders at the epiphysis and fractures have occurred, and post-marketing reports and literature have mentioned slipped capital femoral epiphysis and accelerated growth.

Slipped capital femoral epiphysis is a condition where a slip occurs at the growth plate part of the femur near the hip joint. It cannot be treated as mere "growing pains."

In another report examining adverse skeletal effects in pediatric patients, erdafitinib was discontinued in all five analyzed cases, and surgical intervention was required in three cases. However, it is not possible to calculate the incidence rate for all users from such case reports.

In cancer treatment, drugs are chosen by comparing the severity of the disease with the benefits and risks of the drug. Just because a drug is used in such treatments does not justify its use by healthy individuals to change their appearance.

Reactions on Social Media—Expectations, Interest in Acquisition, and Voices of "It Didn't Work"

Looking at actual online discussions, the reactions are not uniform.

In Reddit's "Biohackers" community, posts inquiring whether anyone has tried FGFR inhibitors for height purposes can be found. The interactions show three major trends.

The first is the expectation of effects. There are posts asking about usage experiences and changes in height, expressing intentions to try it.

The second is interest in acquiring the drug. Replies asking about sources of acquisition accumulate, and discussions about scientific evidence turn into conversations about actual purchases.

The third is experiences or doubts that do not meet expectations. Posters who had announced their intention to use the drug later report that, honestly, they do not think they have grown taller. There are also questions confirming basic mechanisms, such as whether it works after the growth plates have closed.

These are anonymous self-reports, and age, actual usage, product content, and physical changes cannot be independently verified. It is also not possible to judge the scale of the trend among young people from a few posts.

Nevertheless, it can be inferred that there are situations where interest in acquisition and use precedes, even when medical uncertainties remain.

Additionally, in the reader comments section of the attached Daily Mail article, there were opinions suggesting that men and boys should not determine their value based on whether they are seen as attractive by others. This is a reader reaction separate from social media posts, but it is a voice that focuses on the issue of self-evaluation behind the drug's dangers.

The Moment "There's a Paper" Becomes "It's Safe for Me"

This issue is not spreading based solely on baseless rumors. The existence of actual papers makes it difficult to interpret the information.

"Growth acceleration was observed in children undergoing treatment."

This observation turns into information online that "there is a drug that can make you taller," and further leads to the expectation that "it should be usable for me too."

What gets lost along the way are the conditions of the disease and treatment history of the research subjects, the small number of cases, bone abnormalities, and unknown long-term results.

This is the issue of information reinterpretation visible from the current materials. The existence of a paper itself does not prove the appropriateness of using the drug for a specific purpose.

What needs to be confirmed is not just "is there research," but "who was it used for, for what purpose, and what benefits and harms were confirmed in the research."

When Concerned About Height in Japan, First Look at Growth Progress

This issue cannot be dismissed as a distant overseas news story for Japanese children and parents. However, it cannot be concluded from the current materials that the same drug use is spreading in Japan.

The Japanese Society for Pediatric Endocrinology recommends recording growth curves if concerned about a child's height. The focus should be not only on current height but also on how it has grown over time.

Being shorter than average does not immediately determine the necessity of treatment or indicate a disease. On the other hand, if growth is poor, there may be an underlying disease.

If there are concerns, bring records of height and weight from school health checkups and consult with a pediatrician or pediatric endocrinology specialist. It is more important to continuously evaluate the individual's growth than to compare it with success stories online.

If you are already self-administering drugs for height purposes, do not continue taking them based on self-judgment. Instead, inform medical institutions of the drug's name and usage situation and consult them. If there are visual changes or severe bone or joint pain, immediate medical attention is necessary. Those prescribed the drug for cancer treatment should not stop on their own and must consult their primary doctor.

To Stop Dangerous Methods, Don't Dismiss the Concerns

Simply being surprised by "why would anyone do something so dangerous" will not bridge the gap with young people concerned about their height.

For them, daily comparisons, teasing, and anxieties about romance may feel heavier than adults around them realize. This case shows that such concerns can lead to choices that endanger the body.

What is needed is both clearly communicating the dangers of the drug and taking the concerns seriously.

Avoid making repeated jokes about height. Do not associate being tall or short with personal superiority or inferiority. Instead of dismissing concerns with "don't worry about it," listen to what is troubling them. If there are medical concerns, connect them with specialists.

What should be delivered to young people hoping for a few centimeters of change is not a method that risks health, but an opportunity to correctly understand their growth and the realization that they are respected even with their current body.

Sources and References

1. Daily Mail:Published on November 12, 2026. Introduces the use of erdafitinib for height purposes by teenagers, warnings from doctors, and content from Rolling Stone interviews.
   https://www.dailymail.com/health/article-16284645/heightmaxxing-teens-cancer-drug-warning.html

2. Hormone Research in Paediatrics: Case report on growth acceleration during erdafitinib treatment
   Observation of two children with central nervous system tumors. Published online in 2024, included in the 2025 volume. Reports on growth acceleration and bone changes, not a trial verifying efficacy in healthy young people.
   https://pmc.ncbi.nlm.nih.gov/articles/PMC12668719/pmc.ncbi.nlm.nih.gov

3. DailyMed: U.S. prescription information for BALVERSA (erdafitinib)
   Information on approval targets, eye disorders, hyperphosphatemia, unestablished safety and efficacy in children, and adverse skeletal effects.
   https://www.dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2a8aa5c0-6c92-4566-8c45-e8f4d1fc20eeBALVERSA- erdafitinib tablet, film coated

4. Postmarketing Cases of Erdafitinib-Associated Skeletal Growth Toxicity Events in Pediatric Patients
   Report examining five cases of adverse skeletal growth events in pediatric patients. References cases requiring drug discontinuation or surgical intervention.
   https://pmc.ncbi.nlm.nih.gov/articles/PMC13008465/pmc.ncbi.nlm.nih.gov

5. Reddit・r/Biohackers: Public thread on FGFR inhibitors and height
   Used to confirm online reactions, including expectations of use, interest in acquisition sources, and posts claiming no perceived effects. Anonymous posts are not treated as medical evidence.
   https://www.reddit.com/r/Biohackers/comments/1t0wesa/fgfr3_inhibitors_for_height_growth/reddit.com

6. The Japanese Society for Pediatric Endocrinology: General Q&A
   Reference for checking growth curves, individual differences in height growth, and consultation with pediatricians or pediatric endocrinology specialists.
   https://jspe.umin.jp/public/QandA.htmljspe.umin.jp

7. The Japan Endocrine Society: Growth Hormone Deficiency Short Stature
   Reference for evaluating short stature and explaining that being short does not immediately mean disease or treatment necessity.
   https://www.j-endo.jp/modules/patient/index.php?content_id=80