Ketoconazole (Generic Name)

Other names: Nizoral

About This Drug

High-dose ketoconazole is used to treat prostate cancer. It is given by mouth (orally).

Possible Side Effects

  • Stomach pain
  • Decreased appetite
  • Skin problems. You may develop a rash, dry skin, or itching. The skin on your elbows, legs, underarms, and in other folds of your skin may feel sticky.
  • Changes in your nails. Your fingernails and toe nails may become dry or cracked. They may grow more slowly.
  • Diarrhea
  • High blood pressure
  • Changes in liver enzymes. Your doctor will check your liver enzymes as needed.
  • Swelling of your legs, ankles, and/or feet
  • Breast swelling, tenderness, and pain
  • Hot flashes
  • Weakness

Treating Side Effects

  • Ask your doctor or nurse about medicine to help prevent or lessen nausea, vomiting, diarrhea, pain, or itching.
  • If you vomit or have diarrhea, you are at risk for dehydration. To prevent dehydration, drink plenty of fluids, unless your doctor has told you to limit your fluid intake because of another medical condition.
  • Do not put anything on your rash unless your doctor or nurse says you may. Keep the area around the rash clean and dry.

Important Information

Take this drug with food to help lessen nausea and vomiting.

Food and Drug Interactions

  • There are no known interactions of ketoconazole with food.
  • This drug may interact with other medicine. Drugs that treat heartburn and stomach upset such Maalox®, Mylanta®, Protonix®, Nexium®, Prilosec®, Pepcid®, Tagamet®, and Zantac® may decrease the effect of your cancer treatment if taken with ketoconazole. Call your doctor to find out what drug you may take with ketoconazole to help with heartburn or stomach upset.
  • Talk with your doctor about taking St. John’s Wort, garlic, ginseng, and ginkgo. Tell your doctor and pharmacist about all the medication and dietary supplements (vitamins, minerals, herbs and others) that you are currently taking. The safety and effectiveness of dietary supplements and alternative diets are often unknown. Using these might unexpectedly affect your cancer or interfere with your treatment. Until more is known, you should not use dietary supplements or alternative diets without your cancer doctor's advice.

When to Call the Doctor

Call your doctor or nurse immediately if you have any of the following symptoms:

  • Uncontrolled nausea that prevents you from eating or drinking
  • Vomiting more than 3 times a day
  • Diarrhea more that 4 times a day or diarrhea with weakness or lightheadedness
  • Confusion
  • Trouble waking up
  • Severe headache
  • Stomach pain
  • Signs of liver problems: dark urine, pale stools, severe stomach pain, severe tiredness or weakness, unusual itching, or yellowing of the eyes or skin

Call your doctor or nurse as soon as possible if you have any of the following symptoms:

  • Nausea, vomiting, itching, rash or other skin problemsthat prescribed medicine does not help
  • Persistent loss of appetite or rapid weight loss (more than 5 pounds in a week)
  • Extreme weakness that interferes with normal activities
  • Muscle pain or weakness
  • Swelling of your legs, ankles, or feet
  • Breast swelling, tenderness or pain that is bothersome

Reproductive Concerns

Pregnancy warning: It is not known if this drug may have harmful effects on an unborn child. For this reason, be sure to speak with your doctor if you are pregnant or planning to become pregnant while receiving this drug.

Breast feeding warning: Women are advised not to breast feed during treatment because this drug could enter the breast milk and seriously harm the breastfeeding infant. In men, it may cause impotence or erectile dysfunction which means he is not able to have a sexual erection or maintain it as he was able to before taking this drug. Talk with your doctor if this occurs.

Revised: June 2013

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