Ketoconazole (Oral)


Ketoconazole is used in the treatment of serious yeast or fungal infections, such as candidiasis (oral thrush, thrush), coccidioidomycosis (San Joaquin Valley fever, Valley fever,), blastomycosis (Gilchrist's disease), histoplasmosis (Darling's disease), chromoblastomycosis (chromomycosis), or paracoccidioidomycosis (Lutz-Splendore-Almeida disease, South American blastomycosis). This medication works by killing the yeast or fungus and/or preventing the growth.

This medication is also used to treat parasitic fungal infections on the skin (such as ringworm or athlete's foot) that can't be treated with griseofulvin or topical medication, or for patients who cannot take griseofulvin. You cannot obtain this medication alone, it can only be given via prescription from a doctor. It is available in the dosage form of tablet for oral consumption.

Conditions treated

  • Coccidioidomycosis

Type of medication

  • Oral tablet

Side effects

Alongside the intended effects of this medication, its consumption could produce a variety of unwanted side effects. Some of these may or not be present, however, if they are present, you may need to seek medical advice.

Seek professional advice if you suffer from any of the following side effects whilst taking Ketoconazole:


  • Trouble sleeping

Some side effects that may occur with this drug, don't typically require any medical attention. In most circumstances, these side effects will begin to reduce or disappear as your body begins to adjust to the medication. However, if you are finding the side effects bothersome, you can contact your local pharmacist for advice on ways to avoid these side effects. You should seek advice from your doctor if any of the following side effects listed below become persistent or bothersome.


  • Loss of sexual ability, drive, desire or performance

It is possible that you may suffer from other side effects that are not listed above. You should check with your doctor if you notice anything alarming or unusual. You can also report all your side effects to the FDA on 1-800-FDA-1088 if you wish.


The final dose of any medication will depend on different factors. Your doctor will take into account the strength of the medication, how long you will be required to take the medication and your reaction to the first dose. They will also consider personal factors such as your weight, age and height, any other medical conditions you may suffer from and any other medications you are taking to treat those conditions. It's very important that you do not change your dose without speaking with your doctor first. This is because to do so could increase your risk of severe interactions and side effects, or reduce the effectiveness of the drug in treatment. Do not share your medication with anyone else.

For oral dosage form (tablets) for the treatment of fungal infections:


An initial dose of 200 milligrams once daily. Your doctor can increase your dose as necessary.

Children two years of age and older: The final dose will be determined by your body weight and will be set by your doctor. Typically, the dose is 3.3 to 6.6 milligrams per kilogram of weight each day.

Children younger than two years of age: The dose and use will be determined by a doctor or healthcare professional.

Missed Dose

If you miss a dose of Ketoconazole, you should take it as soon as you've realized. This is unless it's almost time for your next dose. On this occasion, you should skip the dose you have missed and revert back to the normal dosing schedule. Don't double your doses to rectify a missed dose.

Proper Use

Do not stop taking this medication without discussing it with your doctor or healthcare team first. To do so could hinder your treatment.

This medication should come alongside a Medication Guide. You should follow and read these instructions and ask your doctor if you've got any queries or questions.

It's best to take this medication alongside the consumption of food.

Even if you start to feel better after a few doses, it's important that you keep using this medication for the full treatment time. Your infection may not clear up if you stop using this medication too soon.

If you are taking this drug alongside an antacid-containing aluminium, it needs to be taken with an acidic drink. Any antacid-containing aluminium should be taken at least one hour before or two hours after taking this medication.


This drug can interact with a number of other medications. These interactions could produce serious reactions or reduce the use of this drug in treatment. In order to help limit the risk of these interactions occurring, it's vital that your doctor or healthcare team are aware of any other medications you are taking. This should include all herbal products, vitamin supplements and over the counter drugs (prescription and nonprescription drugs). They should also be made aware of any other medical conditions you may suffer from as these too can increase your risk of interactions. In most cases, your doctor will avoid treating you with this drug to limit interactions.

The use of this medication alongside any of the following medicines is not typically recommended. Your doctor may avoid treating you with this drug altogether or change some of the other drugs you are taking.

  • Lomitapide

The use of this medication alongside any of the following drugs is not typically recommended. However, in some cases, it may be necessary. If you are given both medications together, your doctor may adjust the dose or frequency in which you use either medicine.

  • Nifedipine

The use of this medication alongside any of the following medications can cause an increased risk of some side effects, however, this may still be the best treatment option for you. If you are given both medications at the same time, your doctor may change how often you use either drug or change the dose.

  • Acenocoumarol

Other interactions

Some medications cannot be used at or around the time of consuming food as interactions may occur. The use of tobacco or alcohol with certain medications can also increase the risk of interactions.

The use of this medication with any of the following is not usually recommended, but in some circumstances, it may be unavoidable. If you use these items together, your doctor may change your dose or frequency in which you use this medication or give you specific instructions about the use of this medication with food, tobacco or alcohol.

  • Grapefruit Juice

Other medical conditions

If you suffer from other medical problems, these too could limit the effectiveness of this medication and increase the risk of interactions. You should let your doctor know if you suffer from any other medical conditions, especially:

  • Adrenal problems


Before you decide to take Ketoconazole, there are a number of things you should consider alongside the advice of your doctor. Some of these considerations are placed below.


You should make your doctor or healthcare team aware if you've ever suffered from an allergic reaction to this medication or similar medications. You should also let them know about any other allergies you may suffer from including to animals, dyes, foods or preservatives.

Pediatric population

Appropriate studies have not been conducted on the relationship of age to the effects of ketoconazole in young children of two years old. Therefore efficacy and safety have not been established.

Geriatric population

There is currently no information available on the relationship of age to the effects of ketoconazole in the elderly population. Therefore safety and efficacy have not been established.

Use in pregnancy and breastfeeding

This drug is under FDA pregnancy category C. It is currently unknown whether this medication can harm an unborn child. You should tell your healthcare team if you are pregnant.

This drug can pass into breast milk and can cause harm to a nursing child. You should avoid breastfeeding while using this medication.

It's extremely important that your doctor monitors your or your child's progress at regular appointments to ensure this medication is working correctly. Your doctor may perform urine or blood tests to check for unwanted side effects.

If your symptoms don't improve, or if they worsen, you should seek advice from your healthcare professional or a doctor. You may be required to take this medication for several months before your infection begins to improve and clear.

Do not use this medication in combination with any of the following medications:

  • Ergot medicines (such as ergometrine, dihydroergotamine, ergotamine, methylergometrine).
  • Dronedarone

The use of these medications together could produce serious side effects.

Liver problems could potentially occur whilst you are taking this drug. You should check with your doctor immediately if you are having more than one of these symptoms:

  • Unusual weakness or tiredness

Contact your doctor immediately if you have any changes to your heart rhythm. You may feel faint or dizzy, or you might have a pounding, fast, or uneven heartbeat. Ensure that your doctor knows if you or anyone in your family has ever had problems with heart rhythm such as QT prolongation.

This medication could cause a serious allergic reaction, including anaphylaxis. This can be life-threatening and requires urgent medical attention. Call your doctor immediately if you have itching, a rash, trouble breathing, difficulty swallowing, or any swelling of your face, hands, or mouth while you are using this medication.

Don't drink alcohol whilst you are using this drug.


Ketoconazole should be stored in a closed container and kept away from direct light, moisture and heat. You should not let this medication freeze. Keep this drug out of the reach of children and dispose of any medication you no longer need or has passed its expiry date. Your local pharmacist will be able to give you advice on the best method of disposal for any medication you no longer need.


When used correctly and as directed, Ketoconazole is successful in the treatment of a variety of serious yeast and fungus infections. However, due to the vast number of interactions possible with this drug, it's imperative that you give your healthcare team a list of every medication you are currently taking.

This safety and efficacy of this drug have not been established in children under the age of two years old and in the older population. It's unknown whether this drug can harm an unborn child, but you should let your doctor know if you are pregnant. This drug can pass into breast milk so you should avoid breastfeeding whilst taking it.

You should take this drug at the same time each day. Continue to take Ketoconazole until the full prescribed amount is complete, even if you begin to feel better. If you stop this drug too early, your infection could return. You should let your doctor know if your condition becomes worse or stays persistent. Do not consume alcohol whilst using this drug, you may put yourself at risk if you do so as this drug can cause serious liver damage. If you require any further information about the practical uses of this drug or you have any questions, you should contact your local doctor or healthcare professional for further advice.