A striking increase in prescribing of testosterone
occurred over the first decade of this century, with
a 10-fold increase in testosterone prescriptions per
capita in the United States (excluding compounding
The 40-fold increase in Canada, which includes
internet pharmacies providing additional
testosterone sales, suggests that this may be an
Yet pathological hypogonadism, defined as recognised
pathological disorders of the male reproductive
system, remains the sole unequivocal indication for
In a recent study researchers examined data on
19,215 patients with blood clots (comprising deep
venous thrombosis and pulmonary embolism) and more
than 900,000 similar men without a history of clots
collected from 2001 to 2013 in the U.K. to determine
the risk of venous thromboembolism associated with
use of testosterone treatment in men, 909,530 age
matched controls from source population including
more than 2.22 million men.
In the first six months after starting testosterone,
men have a 63 percent higher risk of clots in the
legs and lungs than they did before beginning
treatment, the study found: the risk peaked within
six months and declined thereafter.
Testosterone levels decline gradually over time,
leading to symptoms such as decreased libido, sexual
dysfunction, decreased bone mineral density, mood
disorders, reduced muscle mass and fatigue.
Most of these symptoms can also come from other
causes such as diabetes, high blood pressure, heart
disease and thyroid disorders.
Millions of men worldwide have taken testosterone to
address these symptoms.
Some previous studies suggest a possible
relationship between low testosterone and hardening
of the arteries, heart disease, and blood clots,
said Dr. Joao Zambon, a researcher at Wake Forest
University in Winston-Salem, North Carolina who
wasn't involved in the study.
For more information
Testosterone treatment and risk of venous
thromboembolism: population based case-control study