Drug Types, Dosage Information, Method of Action, Side Effects and Precautions for Prostate Cancer Drugs

Medications used to treat prostate cancer include estrogens, luteinizing hormone-releasing hormone (LHRH) agonists, luteinizing hormone-releasing antagonists and antiandrogens. Here is some information about usual daily doses, how to take these medicines, how the drugs work, side effects and precautions. The dosages represent an average range for the treatment of prostate cancer. The precise effective dosage varies from person to person and depends on many factors. Do not make any changes to your medication without consulting your doctor.

Estrogens to Treat Prostate Cancer

  • Premarin (estrogen, conjugated)—1.25-2.5 mg 3 times per day; taken at the same time every day.

    Estrogen blocks the release of luteinizing hormone-releasing hormone (LHRH) from the hypothalamus, preventing the action of luteinizing hormone (LH), which signals the testicles to produce testosterone. This treatment requires 2 weeks to lower testosterone to the castrate range. If estrogen is discontinued, testosterone levels will return to normal. Do not take estrogen if you have liver disease. This drug may increase risk of cardiovascular problems, including heart attack and blood clots.

    Side effects include

    • breast enlargement
    • nausea
    • vomiting
    • fluid retention
    • erectile dysfunction
    • loss of libido

    Call your doctor if you develop sudden changes in vision or speech, severe headaches, leg pains, dizziness or faintness.

    LHRH Agonists to Treat Prostate Cancer

    • Eligard, Lupron, Viadur (leuprolide)—Lupron: 7.5/22.5/30 mg injected every 1, 3, or 4 months, respectively; Eligard: Same as Lupron and 45 mg injected every 6 months; Viadur: One 65-mg implant every 12 months
    • Trelstar Depot (triptorelin), Trelstar LA (triptorelin)— 3.75 mg injected every month or 11.25 mg injected every 3 months 0r 22.5 mg injected every 6 months
    • Zoladex (goserelin)— 3.6 mg injected every month or 10.8 mg injected every 3 months

    Initially, these drugs stimulate the pituitary to release LH, prompting a jump in testosterone production. After several weeks, they block LH formation, and testosterone levels fall to castrate range.

    LHRH agonists may cause a temporary increase in cancer symptoms such as pain, urinary blockage, or weakness of the legs. They may increase risk of diabetes and cardiovascular disease. (Pose less cardiovascular risk than estrogens.) Your doctor should monitor you for these conditions. Viadur: Implant must be removed after 12 months. It may be replaced by a new implant to continue therapy.

    Side effects include:

    • sweating
    • hot flashes
    • weight gain
    • fatigue
    • erectile dysfunction
    • loss of libido
    • loss of bone and muscle mass
    • headache
    • transient increase in cancer symptoms
    • mild pain
    • bruising or itching at injection or implant site

    If you are taking Eligard or Lupron, call your doctor if you develop

    • hives
    • rash
    • itching
    • difficulty breathing or swallowing
    • numbness, tingling, weakness, or pain in the feet or lower legs
    • painful or difficult urination
    • blood in urine
    • bone pain
    • testicular or prostate pain
    • inability to move arms or legs

    If you are taking Viadur, call your doctor if you experience any of the above symptoms or unusual bleeding, redness or pain at the insertion site. If you are taking Trelstar and Zoladex, call the doctor if you develop

    • rash
    • itching
    • swelling
    • severe dizziness
    • trouble breathing
    • sudden severe headache
    • vomiting
    • visual changes soon after injection

    LHRH Antagonists to Treat Prostate Cancer

    Firmagon (degarelix)—240 mg, then 80 mg injected every month

    LHRH antagonists block the production of gonadotropin-releasing hormone (GnRH) by the pituitary gland, which prevents GnRH from stimulating the testes to produce testosterone. Tell your doctor if you have any heart, kidney, or liver problems or problems with the balance of your body salts or electrolytes. This drug can elevate liver enzymes; liver function should be tested during use.

    Side effects include

    • pain, redness and swelling around the infection site
    • hot flashes
    • flushing of the skin
    • weight gain
    • fatigue
    • increase in some liver enzymes

    Call your doctor if you gain weight unexpectedly, feel more tired than usual, experience back or joint pain, develop chills or symptoms of a urinary tract infection, have decreased sex drive or erectile dysfunction.

    Antiandrogens to Treat Prostate Cancer

    • Casodex (bicalutamide)—50 mg daily; taken at the same time every day, with or without food. Used with an LHRH analog.
    • (flutamide) (generic only)—750 mg daily; Two 125-mg tablets every 8 hours. Used with an LHRH analog.
    • Nilandron (nilutamide)—300 mg daily for 30 days, then 150 mg daily; taken with or without food. Used in combination with LHRH analogs or surgical castration, because antiandrogens are not as effective when used alone.

    Antiandrogens bind to the same cellular receptors that androgen hormones (including testosterone) use to stimulate prostate cells. Thus, they prevent androgen hormones from affecting the prostate.

    These drugs are known to cause liver damage; liver function must be checked. May interact with several drugs, including cholesterol-lowering medications and anticoagulants such as warfarin. Nilandron also carries a risk of lung damage; a routine chest x-ray is required before first dose. Avoid alcohol if use coincides with flushing or other symptoms. Users may have trouble adjusting to the dark. Use caution while driving through tunnels and at night. Tinted glasses may help.

    Side effects include hot flashes, pain in the back or pelvis, and diarrhea. Nilandron also may cause constipation. Call your doctor if you experience

    • nausea
    • vomiting
    • abdominal pain
    • fatigue
    • loss of appetite
    • flu-like symptoms
    • dark urine
    • jaundice
    • tenderness in your right upper abdomen

    If you are taking Nilandron, seek immediate medical attention if you develop shortness of breath, coughing, chest pain or fever.

    Publication Review By: H. Ballentine Carter, M.D.

    Published: 21 Jun 2011

    Last Modified: 19 Feb 2015