Health Library

Ketoconazole (By mouth)

Ketoconazole (kee-toe-KON-a-zole)

Treats fungal infections.

Brand Name(s):

When This Medicine Should Not Be Used:

How to Use This Medicine:

Tablet

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
• It is best to take this medicine with food or milk.
• Take all of the medicine in your prescription to clear up your infection, even if you feel better after the first few doses.
• This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
• Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Do not use this medicine together with alprazolam, cisapride, colchicine, disopyramide, dofetilide, dronedarone, eplerenone, felodipine, irinotecan, lovastatin, lurasidone, methadone, nisoldipine, oral midazolam, pimozide, quinidine, ranolazine, simvastatin, tolvaptan, triazolam, or ergot medicines (such as dihydroergotamine, ergometrine, ergotamine, methylergometrine).
• There are many medicines that can affect how ketoconazole works. Tell your doctor if you are using carbamazepine, colchicine, dasatinib, everolimus, isoniazid, lapatinib, nilotinib, phenytoin, rifabutin, rivaroxaban, salmeterol, sirolimus, tamsulosin, telithromycin, temsirolimus, or warfarin.
• If you take medicine to reduce stomach acid (such as antacids), take it at least 1 hour before or 2 hours after you take ketoconazole.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant, or if you have liver disease, heart rhythm problems (such as QT prolongation), adrenal problems, or stomach problems.
• Do not breastfeed while you are using this medicine.
• This medicine may cause the following problems:
  • Liver problems
  • Changes in heart rhythm, such as a condition called QT prolongation
• Do not drink alcohol while you are using this medicine.
• Call your doctor if your symptoms do not improve or if they get worse. Keep all appointments.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Dark urine or pale stools, nausea, vomiting, loss of appetite, pain in your upper stomach, yellow skin or eyes
• Fainting, dizziness, lightheadedness
• Fast, pounding, or uneven heartbeat

If you notice these less serious side effects, talk with your doctor:

• Headache
• Problems having sex
• Swollen breasts (in males)

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024