An agonist is a
chemical agent which mimics the action of a naturally-occurring
chemical. When used as a hormone
therapy in prostate cancer treatment, the specific
agonist used is called GnRH agonist or LHRH agonist.
The hormone that the LHRH agonist is mimicking is called
LHRH. In this form of prostate cancer treatment, the
LHRH agonist enters the receptors of the pituitary gland.
The pituitary gland begins to make LH which tells the
testicles to begin producing more hormones. The result
is called tumor flare which is a spike in the body’s
level of testosterone which lasts 7 to 10 days. Tumor
flare can be extremely painful and even dangerous for
prostate cancer patients with bone
metastasis. After the flare, the levels of testosterone
in the body will drop to castrate levels because the
LHRH agonist continues to occupy the receptors.
For prostate cancer patients without bone metastasis, LHRH agonists are good choices for hormone therapy. The tumor flare will not turn cause the disease to become more aggres