Guide to Abiraterone

If you’ve been prescribed abiraterone — the generic version of Zytiga — for advanced prostate cancer, this guide will walk you through what the medication is, how it works, how to take it correctly, what to expect, and how to manage costs. Abiraterone has been an important treatment option for advanced prostate cancer since its FDA approval in 2011, and the generic version has been available since 2018.

This guide is for patients and caregivers. It’s been medically reviewed by Julia Kravtsova, PharmD, Head Patient Navigator at QuickRx Specialty Pharmacy.

What Is Abiraterone?

Abiraterone (also called abiraterone acetate) is the generic name of Zytiga, an oral medication used to treat advanced prostate cancer. It belongs to a class of drugs called androgen biosynthesis inhibitors — sometimes also called “adrenal inhibitors” or “anti-androgens.”

Abiraterone is not chemotherapy. It’s a form of hormone therapy. While both are cancer treatments, they work very differently. Chemotherapy attacks rapidly dividing cells throughout the body; hormone therapy like abiraterone targets the hormonal pathway that fuels prostate cancer growth.

Abiraterone is FDA-approved to treat:

• Metastatic castration-resistant prostate cancer (mCRPC) — prostate cancer that has spread and no longer responds to traditional testosterone-lowering treatments
• Metastatic high-risk castration-sensitive prostate cancer (mCSPC) — newly diagnosed advanced prostate cancer that still responds to hormone therapy

Abiraterone is taken in combination with prednisone (a corticosteroid) and either a GnRH analog or after surgical castration (bilateral orchiectomy). It is not a cure, but according to the National Cancer Institute, it can slow disease progression and improve survival in many patients.

How Does Abiraterone Work?

Prostate cancer cells need testosterone — and other male hormones called androgens — to grow. Abiraterone works by shutting down the body’s ability to produce these hormones at three different sites simultaneously.

The medication blocks an enzyme called CYP17 (specifically CYP17A1), which is essential for producing testosterone. CYP17 is found in three places in the body:

1. The testes — the primary site of testosterone production in men
2. The adrenal glands — which produce smaller amounts of androgens
3. The prostate tumor itself — advanced prostate cancer cells can produce their own androgens to fuel growth

By blocking CYP17 at all three locations, abiraterone deprives prostate cancer cells of the hormones they need to grow. This is what makes abiraterone different from older hormone therapies, which only addressed testosterone produced by the testes.

Why is prednisone always prescribed alongside abiraterone? When abiraterone blocks CYP17, it also reduces cortisol production. Cortisol is a stress hormone your body needs. Low cortisol can cause side effects like high blood pressure, fluid retention, and low potassium. Prednisone replaces the lost cortisol and helps prevent these side effects.

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Abiraterone Dosage

The standard prescribed dose for most patients is:

• Abiraterone: 1,000 mg once daily (typically four 250 mg tablets, or two 500 mg tablets)
• Prednisone: 5 mg once or twice daily, depending on which type of prostate cancer you have

Per Drugs.com and FDA prescribing information:

• For castration-resistant prostate cancer (CRPC): prednisone 5 mg twice daily
• For castration-sensitive prostate cancer (CSPC): prednisone 5 mg once daily

When dose adjustments are needed

Your doctor may adjust your dose if:

• You have moderate liver impairment (Child-Pugh B): Starting dose reduced to 250 mg once daily
• You have severe liver impairment (Child-Pugh C): Abiraterone is not recommended
• You develop hepatotoxicity (signs of liver stress) during treatment: Your doctor may pause treatment and restart at a lower dose (typically 750 mg) once liver tests return to normal

Never adjust your own dose. If you miss two or more doses, contact your healthcare provider before resuming.

How to Take Abiraterone Correctly

Taking abiraterone the right way is just as important as taking it consistently. Done wrong, the medication can become dangerous instead of effective.

The empty-stomach rule (this matters more than patients realize)

Abiraterone must be taken on an empty stomach:

• No food for at least 2 hours before taking your dose
• No food for at least 1 hour after taking your dose
• Take with water only — swallow tablets whole, do not crush or chew

Why this matters: Taking abiraterone with food dramatically increases how much of the drug enters your bloodstream. Studies cited in the FDA prescribing information show that taking abiraterone with a low-fat meal increases blood concentrations approximately 7-fold, and a high-fat meal increases them up to 17-fold. That’s far more medication than your body is supposed to absorb — and the higher dose can cause serious cardiovascular and liver side effects.

Practical tips for taking abiraterone

• Take it at the same time every day — most patients pick first thing in the morning, before breakfast
• Set a phone alarm for both your dose and when you can eat again
• Keep tablets in their original packaging until you take them — do not handle broken tablets if you are pregnant or may become pregnant (the medication can be absorbed through skin)
• If you miss a dose: Skip it. Take your next dose at the usual time. Do not double up.
• If you miss more than two doses: Contact your healthcare provider before continuing.

Foods and Substances to Avoid

While taking abiraterone:

Avoid completely

• Grapefruit and grapefruit juice — interferes with the liver enzymes that metabolize abiraterone, raising drug levels in your bloodstream and increasing side effect risk
• Alcohol — can worsen liver toxicity and gastrointestinal side effects

Use caution with

• High-fat meals near your dose — see the empty-stomach rule above
• St. John’s wort and other herbal supplements — can reduce abiraterone effectiveness
• Excessive sodium — abiraterone can affect blood pressure; high-sodium diets compound this

Drug Interactions to Know About

Abiraterone interacts with several common medications. Always tell your oncology team about every prescription, over-the-counter drug, vitamin, and supplement you take.

Strong CYP3A4 inducers — avoid if possible

Drugs that strongly activate the CYP3A4 enzyme can reduce abiraterone’s effectiveness by up to 55%, according to clinical pharmacokinetic studies. These include:

• Rifampicin (rifampin)
• Rifabutin
• Rifapentine
• Phenytoin
• Carbamazepine
• St. John’s wort

Other interactions to discuss with your doctor

• Diabetes medications — abiraterone can lower blood sugar, requiring dose adjustments
• Blood pressure medications — abiraterone often raises blood pressure, which may need to be managed
• Anticoagulants (blood thinners) — may need monitoring

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What to Expect During Treatment

How long does abiraterone take to work?

PSA response time varies by patient. In clinical trials, significant PSA reductions were observed as early as 2 weeks after starting treatment, with maximum reductions typically occurring within the first few months.

PSA isn’t the only measure your doctor watches. Imaging, symptoms, and overall blood work all factor into whether abiraterone is working for you. A temporary PSA bump doesn’t necessarily mean treatment failure — sometimes levels fluctuate before settling.

What monitoring is required?

While on abiraterone, you’ll have regular check-ins for:

• Blood pressure (at home and in clinic)
• Potassium and electrolyte levels
• Liver function tests (ALT, AST, bilirubin)
• PSA and other tumor markers
• Blood sugar (especially if you have diabetes)
• Signs of fluid retention or swelling

Your healthcare team will typically check these monthly during the first months of treatment, then less often once you’re stable.

Common side effects

The most commonly reported side effects of abiraterone include fatigue, joint swelling or pain, hot flashes, hypertension, edema (fluid retention), low potassium, and elevated liver enzymes. For a complete discussion of side effects and how to manage them, see our companion guide on Zytiga side effects.

How Much Does Abiraterone Cost?

Abiraterone is one of the most expensive prescription medications in the U.S. The good news is that generic abiraterone is dramatically less expensive than brand Zytiga, and copay assistance programs can reduce out-of-pocket costs even further for eligible patients.

The retail price of brand Zytiga can exceed $10,000 per month — but very few patients actually pay that. Insurance coverage, the switch to generic abiraterone, manufacturer copay programs, and independent foundation grants can all dramatically reduce what you actually pay.

For a free consultation on what copay assistance you may qualify for, visit our abiraterone copay assistance page or call (917) 830-2525.

Related Questions Patients Ask

Is abiraterone the same as Zytiga?

Yes — abiraterone is the generic name of Zytiga. The FDA-approved generic version has been available since 2018 and is bioequivalent to brand Zytiga (same active ingredient, same effectiveness). For more, see our guide to generic Zytiga availability.

Why do I need to take prednisone with abiraterone?

Abiraterone reduces cortisol production along with testosterone. Prednisone replaces the cortisol your body still needs and prevents side effects like high blood pressure, fluid retention, and low potassium.

Can I take abiraterone without prednisone?

No — abiraterone must be taken with prednisone (or prednisolone). Taking it alone significantly raises the risk of serious side effects.

What if abiraterone stops working?

Like all cancer treatments, abiraterone can stop being effective over time as cancer cells develop resistance. Your oncologist may switch you to chemotherapy, immunotherapy, a different hormone therapy, or recommend a clinical trial. See our guide on stopping Zytiga for more.

How does abiraterone compare to Xtandi (enzalutamide)?

Both are hormone therapies for advanced prostate cancer, but they work differently. See our detailed Xtandi vs Zytiga comparison.

How QuickRx Helps Abiraterone Patients

QuickRx Specialty Pharmacy supports prostate cancer patients on abiraterone with:

• Free copay assistance consultation and enrollment
• Insurance benefits verification and prior authorization support
• Coordination with your oncologist’s office
• Nationwide 2-day delivery (licensed in all 50 states)
• Dedicated patient navigators who handle paperwork on your behalf
• Ongoing refill management and renewal reminders

To get started, visit our abiraterone copay assistance page or call (917) 830-2525.

References

1. U.S. Food and Drug Administration. Zytiga (abiraterone acetate) prescribing information. Accessed May 2026.
2. National Cancer Institute. Abiraterone Acetate Drug Information. Available at cancer.gov.
3. MedlinePlus. Abiraterone Drug Information. U.S. National Library of Medicine. Available at medlineplus.gov.
4. Mayo Clinic. Abiraterone (oral route): description and dosage. Available at mayoclinic.org.
5. Drugs.com. Abiraterone Dosage Guide. Available at drugs.com.
6. Memorial Sloan Kettering Cancer Center. Abiraterone Acetate Patient Education. Available at mskcc.org.