Classification: Nonsteroidal Antiandrogen
About: Bicalutamide (Casodex®)
Most prostate cancers need a supply of the male hormone testosterone to grow. Testosterone is an androgen (hormone) produced by the testes and adrenal glands. Bicalutamide works by blocking testosterone receptors on the prostate cells, and therefore preventing testosterone from attaching to the receptors on the surface of the prostate cancer cells. Without testosterone, the cancer cells may either grow more slowly, or stop growing altogether.
How to Take Bicalutamide
Bicalutamide comes in a tablet form and is taken once a day, preferably at the same time each day. Do not break, crush, or chew the tablet. Bicalutamide can be taken with or without food. If you miss a dose, take your next dose at your regular time. Do not take two doses at the same time.
It is important to make sure you are taking the correct amount of medication every time. Before every dose, check that what you are taking matches what you have been prescribed. If you take too much medication, contact your care provider or go to the nearest emergency room.
The blood levels of this medication can be affected by certain foods and medications, caution should be used if this medication is given with warfarin and CYP substrates including but not limited to: Amiodarone, Carbamzapeine, Clarithromycin, Digoxin, Dronedarone, Haloperidol, Isosorbide Dinitrate, Isosorbide Mononitrate, Lurasidone, Macitentan, Methadone, Midazolam, Nicardapine, Ranolazine, Sirolimus, Tacrolimus and certain anti-retroviral therapies. Be sure to tell your healthcare provider about all medications and supplements you take.
Storage and Handling
Store your medication in the original, labeled container at room temperature and in a dry location (unless otherwise directed by your healthcare provider or pharmacist). This medication should not be stored in a pillbox. Keep containers out of reach of children and pets.
If a caregiver prepares your dose for you, they should consider wearing gloves or pour the pills directly from their container into the cap, a small cup, or directly into your hand. They should avoid touching the pills. They should always wash their hands before and after giving you the medication. Pregnant or nursing women should not prepare the dose for you. Ask your oncology team where to return any unused medication for disposal. Do not flush down the toilet or throw in the trash.
Where do I get this medication?
Bicalutamide is available through retail or mail order pharmacy. Your oncology team will work with your prescription drug plan to identify an in-network, retail or mail order pharmacy for medication distribution.
This medication may be covered under your prescription drug plan. Patient assistance may be available to qualifying individuals depending upon prescription drug coverage. Co-pay cards, which reduce the patient co-pay responsibility for eligible commercially (non-government sponsored) insured patients, may also be available. Your care team can help you find these resources, if they are available.
Possible Side Effects
There are a number of things you can do to manage the side effects of bicalutamide. Talk to your care team about these recommendations. They can help you decide what will work best for you. These are some of the most common or important side effects:
There are a few things you can do to help with hot flashes. Several medications have been shown to help with symptoms, including clonidine (a blood pressure medication), low doses of certain antidepressants (such as venlafaxine and fluoxetine), and gabapentin. Talk to your healthcare team about these prescription products to determine if they are right for you.
Non-medical recommendations include:
- Keep well-hydrated with eight glasses of water daily.
- Drink ice water or apply an ice pack at the onset of a hot flash.
- Wear cotton or lightweight, breathable fabrics and dress in layers so you can adjust as needed.
- Exercise on a regular basis.
- Try practicing meditation or relaxation exercises to manage stress, which can be a trigger.
- Avoid triggers such as warm rooms, spicy foods, caffeinated beverages, and alcohol.
Breast Tenderness or Increase in Breast Tissue
An increase in breast tissue (gynecomastia) or breast tenderness may develop. Your healthcare team can suggest medications to relieve the tenderness. In rare cases, radiation can be given to relieve severe tenderness.
Muscle or Joint Pain/Aches and Headache
Your healthcare provider can recommend medications and other strategies to help relieve pain.
Fatigue is very common during cancer treatment and is an overwhelming feeling of exhaustion that is not usually relieved by rest. While on cancer treatment, and for a period after, you may need to adjust your schedule to manage fatigue. Plan times to rest during the day and conserve energy for more important activities. Exercise can help combat fatigue; a simple daily walk with a friend can help. Talk to your healthcare team for helpful tips on dealing with this side effect.
There are several things you can do to prevent or relieve constipation. Include fiber in your diet (fruits and vegetables), drink 8-10 glasses of non-alcoholic fluids a day, and keep active. A stool softener once or twice a day may prevent constipation. If you do not have a bowel movement for 2-3 days, you should contact your healthcare team for suggestions to relieve the constipation.
Low Red Blood Cell Count (Anemia)
Your red blood cells are responsible for carrying oxygen to the tissues in your body. When the red cell count is low, you may feel tired or weak. You should let your oncology care team know if you experience any shortness of breath, difficulty breathing or pain in your chest. If the count gets too low, you may receive a blood transfusion.
Weakening of the Bones (Osteoporosis)
Men who take hormone therapy for extended periods of time are at risk for bone thinning (osteoporosis). You may be advised to get plenty of calcium and vitamin D to reduce your risk of osteoporosis. It is best to get calcium in a balanced diet, including 4-8 servings of calcium rich foods a day. Examples of calcium rich foods are low fat milk, yogurt, cheese, green leafy vegetables, nuts, seeds, beans, legumes and calcium fortified foods and juices. Vitamin D is not present in many foods, so it is harder to get in your diet. Our bodies make vitamin D when the sun hits our skin, but sun avoidance and sunblock prevent many from getting necessary amounts to support bone health. Your care team may recommend supplements of calcium and vitamin D and will tell you how much to take. Weight bearing exercise and strength exercises can also help protect your bone health.
You may have a bone density scan (DEXA scan) to assess your bone health. If your provider determines that you are at high risk of developing osteoporosis, they may recommend additional treatment with a type of medication called a bisphosphonate to help strengthen the bones.
Less common, but important side effects can include:
- Liver Toxicity: This medication can cause liver toxicity, which your doctor may monitor for using blood tests called liver function tests. Notify your healthcare provider if you notice yellowing of the skin or eyes, your urine appears dark or brown or pain in your abdomen, as these can be signs of liver toxicity.
- Mood Changes: Some men report mood swings and depression while on hormone therapy. It can be helpful to talk about concerns and feelings with a partner or close friend. If you find that feelings of sadness are interfering with life, talk with your team about finding a counselor experienced in working with cancer patients.
- Lung Concerns: Patients can develop an inflammation of the lungs (called interstitial lung disease) while taking this medication. Notify your healthcare provider right away if you develop any new or worsening symptoms, including shortness of breath, trouble breathing, cough or fever.
- High Blood Sugar: When taken in combination with LHRH agonists this medication can cause elevated blood sugar levels in patients with and without diabetes. Your oncology care team will monitor your blood sugar. If you develop increased thirst, urination or hunger, blurry vision, headaches or your breath smells like fruit, notify your healthcare team. Diabetics should monitor their blood sugar closely and report elevations to the healthcare team.
Sexual and Reproductive Changes
This drug can affect your reproductive system, resulting in sperm production becoming irregular or stopping permanently. In addition, you may experience erectile dysfunction or a decreased desire for sex during treatment. Talk to your urologist about options for treating erectile dysfunction.
Exposure of an unborn child to this medication could cause birth defects, so you should not father a child while on this medication. Effective birth control is necessary during treatment, even if you believe you are not producing sperm. You may want to consider sperm banking if you may wish to have a child in the future. Discuss these options with your oncology team.