The History of Testosterone Replacement Therapy

Testosterone replacement therapy (TRT) isn’t as modern as it seems.

In fact, TRT has history that stretches back more than 100 years!

What we know today as TRT is the result of decades of research, experimentation, and evolving science around how testosterone affects the body.

From early hormone discoveries to today’s personalized treatment approaches, TRT has evolved significantly over time and continues to.

Here’s how the story goes.

The Origin: Discovering Testosterone

Long before testosterone was identified as testosterone, ancient cultures believed the testes held the secret to strength and vitality.

Through the findings from a Roman scholar by the name of Pliny the Elder, his theories paved the way for the discovery of testosterone.

In one of the first experiments, Arnold Berthuald, a German physiologist, experimented on roosters and made a groundbreaking discovery: the testes appeared to influence the entire body.

From there, testosterone was discovered.

But, Berthuald wasn’t the only one doing experiments.

Things got a little strange in 1889, where a French physiologist named Charles-Edouard Brown-Sequard experimented on himself.

He documented how he ‘rejuvenated’ himself through the testicular extract from guinea pigs.

Later, Brown-Sequard’s extract was found to be pure placebo and ineffective.

Nonetheless, through his experiment, public interest surrounding testosterone exploded.

Paving the Way: Beginning of Testosterone Replacement Therapy (TRT)

In 1929, researchers Adolf Butenandt and Leopold Ruzicka were the first to successfully isolated testosterone, transforming the future of TRT.

In result, testosterone replacement therapy (TRT) was primarily used to treat men with hypogonadism then osteoporosis, as its findings suggested that testosterone can help with bone density and muscle mass.

Testosterone pills were also introduced during this time.

The future looked bright for testosterone replacement therapy (TRT) but as interest grew, so did controversy.

What started as a promising treatment soon found itself at the center of growing stigma and public debate.

Redefining the Stigma

During the 1980’s, the perspective around testosterone changed completely.

A study was released that created the idea that testosterone replacement therapy could risk prostate cancer. Though later disproven, this concept gained attention, changing the public opinion surrounding testosterone replacement therapy (TRT).

Also, during this time, doping scandals were making headlines.

Because of this, Congress passed the Anabolic Steroids Control Act of 1990, scheduling testosterone as a Schedule III controlled substance. The FDA also slapped a black box warning on testosterone warning of cardiovascular disease.

Testosterone then became harder prescribe and unregulated testosterone “boosting” supplements hit the market creating new concerns about safety.

Although testosterone’s reputation had been damaged, scientific advancements and improved clinical practices began to pave the way for a new era of testosterone replacement therapy (TRT).

As researchers gained a deeper understanding of the hormone’s functions in overall health, TRT is starting to be viewed not as a performance-enhancing drug, but as a legit treatment.

TRT of Today & the Future

Today, TRT still carries some lingering stigma, but growing awareness, and the influence of social media has helped challenge outdated myths.

In 2025, the FDA removed the cardiovascular black box warning from all TRT products, following a major clinical trial, marking a significant step forward in how testosterone therapy is viewed and prescribed.

Social media platforms have opened the door for more conversations around hormone health, with both medical professionals and patients sharing their experiences and education, shaping this new era of TRT.

This visibility has helped normalize discussions, encouraging more people to seek facts rather than relying on misinformation. Since 2003, the number of men on TRT has made a steady increase.

As testosterone replacement therapy continues to advance, SynergenX is helping shape the future of hormone therapy.

SynergenX: Leading Testosterone Replacement Therapy (TRT)

Building on decades of research and a deeper understanding of hormone health, testosterone replacement therapy has transformed into a safe, evidence-based treatment option.

What was once misunderstood has now become a key part of modern men’s healthcare.

At SynergenX, our mission is to continue leading that evolution.

As TRT continues to advance, SynergenX remains dedicated to staying at the forefront of innovation and patient care, helping bridge the gap between scientific progress and real-world treatment.

Testosterone’s history has been anything but simple. The next chapter? That’s yours to take control of.

FDA issues class-wide labeling changes for testosterone products | FDA

PLINY THE ELDER, Natural History | Loeb Classical Library

Award ceremony speech – NobelPrize.org

usrf.org/news/000908-origins.html

USRF – History of Testosterone Replacement Therapy (TRT)

History of testosterone therapy through the ages – PubMed

Trends in Testosterone Replacement Therapy Use from 2003 to 2013 among Reproductive-Age Men in the United States

Medically reviewed by: Micheal Seay, MSN, APRN, FNP-BC

Michael Seay is a Board-Certified Family Nurse Practitioner (FNP-BC) with over 16 years of clinical experience in emergency medicine, urgent care, gastroenterology, geriatric care, and hormone optimization therapy for men and women. He holds a Master of Science in Nursing from Walden University and a Bachelor of Science in Nursing from Platt College School of Nursing. He is certified in hormone pellet placement and weight loss therapies, with a clinical focus on individualized, patient-centered care.