Lupron is the brand name for leuprolide acetate. This drug is a type of hormone therapy that doctors typically use in combination with other treatments to treat people with prostate cancer.

Lupron belongs to a class of drugs called luteinizing hormone-releasing hormone (LHRH) agonists. These medications block the production of LHRH in the body, which results in the testicles producing less testosterone.

Lupron is one of several drugs that doctors may prescribe to help fight prostate cancer by reducing testosterone levels in the body.

In this article, we explore how Lupron works, how effective it is, and what to expect during treatment. We also discuss testosterone flares, side effects, and the outlook for people with prostate cancer.

How does it work?

Injection of lupron for prostate cancer
A doctor will administer Lupron as a small implant injected under the skin.

Lupron and other LHRH agonists are forms of hormone therapy. For people with prostate cancer, the aim of hormone therapy is to reduce testosterone levels in the body.

Male hormones, such as testosterone, encourage the growth of prostate cancer cells. Therefore, lowering testosterone levels in the body can help slow the progression of prostate cancer.

Doctors typically prescribe hormone therapy for people with late-stage prostate cancer or prostate cancer that returns. Some doctors use hormone therapy when the disease is in the early stages, but the American Cancer Society (ACS) recommend watching and waiting as the best approach for early-stage prostate cancer.

How effective is it?

Hormone therapies, such as Lupron, are often effective in combination with other treatments for people with late-stage prostate cancer. Many doctors do not recommend hormone therapy during the early stages of this disease.

One potential issue is that prostate cancer can become resistant to LHRH agonists over time in some people.

According to the ACS, doctors may recommend hormone therapies, such as Lupron, for:

  • cancer that comes back after radiation therapy or surgery
  • cancer that has spread too far for radiation therapy or surgery to cure it
  • people who cannot have radiation therapy or surgery
  • shrinking cancer before radiation therapy
  • people who are having radiation therapy and have a high risk of cancer returning after treatment

What to expect during treatment

Doctors often use hormone therapies, such as Lupron, in combination with radiation therapy or other treatments. They may also use it following surgery.

Healthcare professionals administer Lupron as a depot, which is a small implant that they inject under the person’s skin. The individual can often choose an injection site that is suitable for them. Common injection sites include:

  • upper arms
  • outer thighs
  • buttocks

The treatment regimen for Lupron will depend on the individual’s circumstances, and a person can work with their doctor to determine the best dosage. Some typical dosages include:

  • 7.5 mg — one injection every 4 weeks
  • 22.5 mg — one injection every 12 weeks
  • 30 mg — one injection every 16 weeks
  • 45 mg — one injection every 24 weeks

When a person first starts treatment with Lupron, they may have a testosterone flare. Later on, they may experience side effects due to having very low testosterone levels in their body. After treatment stops, testosterone levels begin to return to normal.

Testosterone flares

When a person first takes Lupron, their testosterone levels may rise, or flare, before dropping to very low levels. For some people, particularly those with advanced prostate cancer, a testosterone flare can temporarily cause their symptoms to worsen.

The symptoms of a testosterone flare can include:

  • blockage of the ureters, the tubes that carry urine from the kidneys to the bladder
  • bone pain
  • worsening nerve symptoms
  • spinal cord compression
  • issues with urination

To help prevent a testosterone flare, doctors may also prescribe an anti-androgen drug during the first few weeks of treatment with an LHRH agonist.

Side effects

Man with fatigue and depression caused by lupron
Side effects of Lupron can include hot flashes, depression, and fatigue.

As with any medical treatment, Lupron and other hormone therapies can cause side effects. Many of these side effects are symptoms of having very low testosterone levels.

Possible side effects of hormone therapies, such as Lupron, can include:

  • loss of muscle mass
  • hot flashes
  • fatigue
  • skin irritation at the site of injection
  • erectile dysfunction or loss of sex drive
  • shrunken testicles and penis
  • changes in blood lipids
  • depression
  • osteoporosis
  • mood swings
  • breast tenderness
  • weight gain
  • the growth of breast tissue
  • anemia

A person should discuss any side effects that they are experiencing with their healthcare team. If the side effects are severe, the doctor may recommend changing the dosage or trying a different treatment.

Alternative treatment options

There are several treatment options for prostate cancer, including other LHRH agonists and various types of hormone therapy.

Other LHRH agonists include:

  • goserelin (Zoladex)
  • triptorelin (Trelstar)
  • histrelin (Vantas)

Alternative hormone therapies include:

  • Orchiectomy. Also known as surgical castration, this is a surgical procedure to remove a person’s testicles. The testicles produce most of the body’s testosterone.
  • LHRH antagonists. These drugs work in a similar way to LHRH agonists, but they lower testosterone levels much more quickly. LHRH antagonists are a form of chemical castration, and doctors use them to treat people with advanced prostate cancer.
  • CYP17 inhibitors. In addition to the testicles, other cells in the body produce small amounts of testosterone. CYP17 inhibitors block these cells from making testosterone.
  • Anti-androgens. These drugs prevent testosterone from working in the body. Doctors usually prescribe anti-androgens in combination with other hormone therapies.

The first treatment for people with prostate cancer is often watchful waiting, where a doctor closely monitors a person to see how the disease progresses. Prostate cancer can progress very slowly, and some people may never require any treatment.

If a person’s cancer does progress to more advanced stages, treatment options can include:

  • radiation therapy
  • surgery
  • cryotherapy
  • chemotherapy
  • vaccine treatment

Doctors often use hormone therapies either in combination with or following one of these treatments.

Outlook

doctor speaking to patient in modern office
Survival rates for prostate cancer are generally very high.

As prostate cancer often progresses very slowly, the survival rates for this disease are generally high.

According to the ACS, the overall 5-year relative survival rate for prostate cancer is 98 percent. This statistic means that people with prostate cancer are 98 percent as likely to live for at least 5 years following diagnosis as those without the condition.

However, a person’s outlook can depend on how advanced the disease is when a doctor diagnoses them with prostate cancer.

For people with cancer that has not spread beyond the prostate or has only spread to nearby tissues or lymph nodes, the 5-year relative survival rate is nearly 100 percent. If the cancer has spread to other areas of the body, such as the lungs, liver, or bones, the 5-year relative survival rate is 30 percent.

It is important to note that everyone’s outlook is different and that doctors have based these estimates on the data of men who received a diagnosis between 2008 and 2014.

Summary

Lupron is a type of hormone therapy for prostate cancer. It works by lowering the amount of testosterone in a person’s body, which helps slow the growth of cancer cells.

Doctors often prescribe hormone therapies in combination with radiation therapy or following surgery. They administer Lupron by injecting it under a person’s skin, which they will do between once a month and once every 6 months.

Because Lupron lowers testosterone levels, it can cause a range of side effects. Anyone experiencing severe or concerning symptoms may wish to discuss these with their doctor.