Adverse effect · Leuprolide (leuprorelin)

How common is adverse effects with Leuprolide (leuprorelin)?

A
Grade A — established in humansSame trials + surveillance · effect size: large · adverse
Short answerEstablished in humans. Same trials + surveillance point the same way: a large effect. The consequences of hormone deprivation: hot flushes, loss of libido and bone density, muscle loss, fatigue, and in men a cardiovascular and metabolic risk signal with long-term use. The initial hormone surge can worsen symptoms in the first weeks.

What the studies show

The consequences of hormone deprivation: hot flushes, loss of libido and bone density, muscle loss, fatigue, and in men a cardiovascular and metabolic risk signal with long-term use. The initial hormone surge can worsen symptoms in the first weeks.

“The leuprolide group reported more "hot flashes" (P = 0.00001).”

Verbatim, from the abstractThe Leuprolide Study Group. Leuprolide versus diethylstilbestrol for metastatic prostate cancer. N Engl J Med, 1984

Several well-run randomised trials in people, pointing the same way. You can plan around this. It still says nothing about whether the effect is worth the side effects for you.

  1. 1
    The Leuprolide Study Group. Leuprolide versus diethylstilbestrol for metastatic prostate cancer.N Engl J Med, 1984199 men; the trial that established GnRH agonists in prostate cancer.
  2. 2

In context

Leuprolide is a modified version of GnRH that, given continuously, does the opposite of the natural pulsed hormone: after a brief surge it exhausts the pituitary and shuts down testosterone or oestrogen production almost completely. That makes it a mainstay of advanced prostate cancer, where the 1984 trial that launched it matched the standard oestrogen treatment with far fewer side effects; it is also used for endometriosis, fibroids, central precocious puberty and IVF cycle control. It is a prescription medicine everywhere and prohibited for male athletes.

Leuprolide (leuprorelin) is approved (rx). Legal status differs by country — see the regulation section or the jurisdiction pages.

Questions

Is Leuprolide (leuprorelin) proven to cause adverse effects?
Yes, as far as human trials can show it: Same trials + surveillance. LYO grades this outcome A.
What studies are behind the grade?
The consequences of hormone deprivation: hot flushes, loss of libido and bone density, muscle loss, fatigue, and in men a cardiovascular and metabolic risk signal with long-term use. The initial hormone surge can worsen symptoms in the first weeks.
Is Leuprolide (leuprorelin) approved for this?
Leuprolide (leuprorelin) is an approved medicine (Approved (Rx)); whether this particular outcome is a licensed indication is stated on the compound page's regulation section.

Other outcomes for Leuprolide (leuprorelin)

Written and maintained by LYO Research — how pages are written and checked. Reviewed 10 September 2026. Grades count human evidence only; see how LYO grades. Not medical advice. Correct this page →