What is Abiraterone: Uses, Dosage, Side Effects and More

Abiraterone is a powerful medication specifically designed to treat advanced prostate cancer in men. This oral medication works by blocking your body's production of testosterone, a hormone that fuels certain types of prostate cancer growth.

If you or a loved one has been prescribed abiraterone, you're likely dealing with a challenging diagnosis. Understanding how this medication works and what to expect can help you feel more confident about your treatment journey.

What is Abiraterone?

Abiraterone is a hormone therapy medication that belongs to a class of drugs called androgen biosynthesis inhibitors. It comes as tablets that you take by mouth, usually once daily.

This medication specifically targets an enzyme called CYP17A1, which your body uses to make testosterone and other male hormones. By blocking this enzyme, abiraterone dramatically reduces the amount of testosterone available to fuel cancer cell growth.

You'll often hear your doctor refer to it by its brand name, Zytiga. The medication is always prescribed along with a steroid called prednisone or prednisolone to help prevent certain side effects.

What is Abiraterone Used For?

Abiraterone is primarily used to treat metastatic castration-resistant prostate cancer (mCRPC). This means the cancer has spread beyond the prostate gland and continues to grow despite other hormone treatments.

Your doctor might prescribe abiraterone if your prostate cancer has become resistant to initial hormone therapy treatments like surgical castration or medications that block testosterone production. It's often used when the cancer has spread to other parts of your body, such as bones or lymph nodes.

In some cases, doctors also prescribe abiraterone for high-risk metastatic hormone-sensitive prostate cancer. This is when the cancer has spread but is still responding to hormone therapy, and your doctor wants to use a more aggressive treatment approach from the start.

How Does Abiraterone Work?

Abiraterone works by cutting off the supply of testosterone that prostate cancer cells need to survive and multiply. Think of testosterone as fuel for these cancer cells.

Your body produces testosterone in three main places: your testicles, adrenal glands, and even within the cancer cells themselves. While other hormone therapies might block testosterone from the testicles, abiraterone goes further by blocking production in all three locations.

The medication inhibits an enzyme called CYP17A1, which is essential for testosterone production. By blocking this enzyme, abiraterone can reduce testosterone levels in your blood to nearly undetectable amounts. This creates an environment where prostate cancer cells struggle to grow and spread.

This is considered a strong and effective medication for advanced prostate cancer. Clinical studies have shown it can significantly slow disease progression and extend survival in many patients.

How Should I Take Abiraterone?

Take abiraterone exactly as your doctor prescribes, typically once daily on an empty stomach. You should take it at least one hour before eating or two hours after eating.

Swallow the tablets whole with water. Don't crush, chew, or break them, as this can affect how the medication is absorbed. Taking abiraterone with food can actually increase the amount of drug your body absorbs, which might lead to more side effects.

Your doctor will also prescribe prednisone or prednisolone to take along with abiraterone. This steroid helps prevent a condition called mineralocorticoid excess, which can cause dangerous increases in blood pressure and decreases in potassium levels.

Try to take your medications at the same time each day to maintain consistent levels in your body. If you're having trouble remembering, consider setting a daily alarm or using a pill organizer.

How Long Should I Take Abiraterone For?

You'll typically continue taking abiraterone for as long as it's effectively controlling your cancer and the side effects remain manageable. This could be months or even years, depending on how your cancer responds.

Your doctor will monitor you regularly with blood tests and imaging scans to check how well the medication is working. They'll look for signs that your cancer is progressing, such as rising PSA levels or new areas of cancer spread.

Some patients take abiraterone for several years with good results, while others may need to switch to different treatments sooner. The decision to continue or stop treatment depends on many factors, including your overall health, side effects, and how your cancer is responding.

Never stop taking abiraterone without discussing it with your doctor first. Stopping suddenly could allow your cancer to start growing more rapidly.

What Are the Side Effects of Abiraterone?

Like all cancer medications, abiraterone can cause side effects, though not everyone experiences them. Most side effects are manageable with proper monitoring and supportive care.

Understanding what to expect can help you recognize side effects early and get the support you need. Here are the most common side effects you might experience:

• Fatigue and weakness: This is the most common side effect, affecting about 4 in 10 patients. The fatigue can range from mild tiredness to more significant exhaustion that affects daily activities.
• Joint pain and swelling: About 3 in 10 patients experience joint discomfort, particularly in the hands, feet, or back.
• High blood pressure: The medication can cause your blood pressure to rise, which is why your doctor will monitor it regularly.
• Fluid retention: You might notice swelling in your legs, ankles, or feet as your body retains more fluid than usual.
• Hot flashes: These sudden feelings of warmth and sweating occur because of the dramatic reduction in testosterone levels.

These side effects are generally well-tolerated, and your healthcare team has strategies to help manage them effectively.

Some patients may experience more serious but less common side effects that require immediate medical attention:

• Severe muscle weakness: This could indicate low potassium levels, which can be dangerous if not treated promptly.
• Irregular heartbeat: Changes in heart rhythm can occur, particularly if potassium levels drop too low.
• Severe shortness of breath: This might indicate fluid buildup around the heart or lungs.
• Chest pain: Any new or worsening chest pain should be evaluated immediately.
• Signs of liver problems: Including yellowing of skin or eyes, dark urine, or severe abdominal pain.

While these serious side effects are rare, affecting less than 1 in 20 patients, it's important to know when to seek immediate medical care.

Who Should Not Take Abiraterone?

Abiraterone is not suitable for everyone, and your doctor will carefully evaluate whether it's right for you. This medication is only approved for men with prostate cancer and should never be given to women or children.

You should not take abiraterone if you have severe liver disease, as the medication is processed by the liver and could worsen liver function. Your doctor will check your liver function with blood tests before starting treatment.

If you have a history of heart problems, your doctor will weigh the benefits and risks carefully. The medication can affect heart function and blood pressure, so close monitoring is essential if you have cardiovascular disease.

Certain medications can interact with abiraterone, so tell your doctor about all prescriptions, over-the-counter drugs, and supplements you're taking. This includes blood thinners, seizure medications, and some heart medications.

Abiraterone Brand Names

The most common brand name for abiraterone is Zytiga, manufactured by Janssen Pharmaceuticals. This was the original brand name when the medication was first approved.

Since the patent expired, several generic versions of abiraterone are now available. These generic medications contain the same active ingredient and work the same way as the brand-name version.

Your pharmacy might substitute a generic version unless your doctor specifically requests the brand name. Both versions are equally effective, though some patients prefer to stick with the brand they started with.

Abiraterone Alternatives

If abiraterone isn't right for you or stops working effectively, several other treatment options are available for advanced prostate cancer.

Enzalutamide (Xtandi) is another hormone therapy that works differently from abiraterone. Instead of blocking testosterone production, it prevents testosterone from binding to cancer cells. Some patients switch between these medications if one stops working.

Docetaxel is a chemotherapy drug that's often used for advanced prostate cancer. It works by directly attacking cancer cells rather than blocking hormones. Your doctor might recommend this if hormone therapies are no longer effective.

Newer treatments include medications like apalutamide (Erleada) and darolutamide (Nubeqa), which work similarly to enzalutamide but may have different side effect profiles.

Is Abiraterone Better Than Enzalutamide?

Both abiraterone and enzalutamide are highly effective treatments for advanced prostate cancer, and choosing between them depends on your specific situation. Neither medication is definitively "better" than the other.

Clinical studies have shown that both medications can significantly extend survival and slow disease progression. The choice often comes down to side effect profiles, other health conditions you might have, and how your cancer has responded to previous treatments.

Abiraterone requires you to take it with prednisone and has specific dietary restrictions, while enzalutamide doesn't require a steroid but may cause more fatigue and has a small risk of seizures. Your doctor will consider these factors when making recommendations.

Some patients may eventually receive both medications at different stages of their treatment journey, as cancer cells can develop resistance to one while remaining sensitive to the other.