Nizoral (ketoconazole, keto) is an older drug that has been used as a part of hormone therapy (ADT) for many years. Keto, which is an inexpensive anti-fungal drug had been used for many years as an inhibitor of adrenal androgen synthesis as is abiriterone (Zytiga). Ztiga has been shown to be more effective, however, it is occasionally considered for treatment of metastatic prostate cancer in situations where a man can not afford Zytiga or it is unavailable. The use of Keto in this manner is totally “off label.”
If you decided to try this route you need to also be aware that the FDA has limited usage of Keto oral tablets due to potentially fatal liver injury and risk of drug interactions and adrenal gland problems
The FDA Safety Announcement:
The topical formulations of Nizoral have not been associated with liver damage, adrenal problems, or drug interactions. These formulations include creams, shampoos, foams, and gels applied to the skin, unlike the Nizoral tablets, which are taken by mouth.
Liver Injury (Hepatotoxicity)
Nizoral tablets can cause liver injury, which may potentially result in liver transplantation or death. FDA has revised the Boxed Warning, added a strong recommendation against its use (contraindication) in patients with liver disease, and included new recommendations for assessing and monitoring patients for liver toxicity (see Additional Information sections).
Serious liver damage has occurred in patients receiving high doses of Nizoral for short periods of time as well as those receiving low doses for long periods. Some of these patients had no obvious risk factors for liver disease. The liver injury is sometimes reversible upon stopping the drug, but that is not always possible.
Adrenal Gland Problems (Adrenal Insufficiency)
Nizoral tablets may cause adrenal insufficiency by decreasing the body’s production of hormones called corticosteroids. Corticosteroids are produced by the adrenal glands, which are small glands located on top of each kidney. Corticosteroids affect the body’s balance of water and salts and minerals (electrolytes). Health care professionals should monitor adrenal function in patients taking Nizoral tablets who have existing adrenal problems or in patients who are under prolonged periods of stress such as those who have had a recent major surgery or who are under intensive care in the hospital.
When making any drug decisions it is very important to know as much about the drug as you can learn. There is never a free lunch when ever you take any sort of medication, so CAUTION should always be your guide.
I’d hate to see someone not use keto because of the incomplete info presented here. When keto is used for PC, it is always given with prednisone (just as Zytiga is) and liver enzymes are checked (just as with Zytiga). You made a statement that “Zytiga has shown to be more effective,” but there has never been a head-to-head comparison that would justify such a statement. In fact, in a recent study of keto, it actually had higher progression-free survival than Zytiga did historically (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4430382/). They act in similar ways, inhibiting enzymes necessary for the adrenal synthesis of androgens and other steroids (thus, the adrenal insufficiency that occurs with both); however, Zytiga is able to do that within the tumor as well. Will that eventually translate to a survival benefit? No one really knows. Keto is a whole lot cheaper, and has a similar toxicity profile; however, it would have to be used “off label,” so insurance companies may or may not cover it. At any rate, it’s worth a discussion with one’s oncologist and insurance provider.