Ketoconazole Uses, Dosage, Side Effects, Food Interaction and all others data.

Ketoconazole interferes with biosynthesis of triglycerides and phopholipids by blocking fungal CYP450, thus altering cell membrane permeability in susceptible fungi. It also inhibits other fungal enzymes resulting in the accumulation of toxic concentrations of hydrogen peroxide.

Ketoconazole, similarly to other azole antifungals, is a fungistatic agent which causes growth arrest in fungal cells thereby preventing growth and spread of the fungus throughout the body.

Trade Name Ketoconazole
Availability Prescription only
Generic Ketoconazole
Ketoconazole Other Names Ketoconazol, Ketoconazole, Ketoconazolum, Ketozole
Related Drugs fluconazole, Diflucan, itraconazole, amphotericin b, voriconazole, Nizoral, Sporanox, Abelcet, Fungizone
Weight 2%w/w, , 200mg, 2%, 2%cleanser, 1%, 400mg
Type Solution, Oral Tablet, Topical Cream, Topical Foam, Topical Gel, Topical Kit, Topical Shampoo, Tablet
Formula C26H28Cl2N4O4
Weight Average: 531.431
Monoisotopic: 530.148760818
Protein binding

Ketoconazole is approximately 84% bound to plasma albumin with another 15% associated with blood cells for a total of 99% binding within the plasma.

Groups Approved, Investigational
Therapeutic Class Drugs for subcutaneous and systemic mycoses
Manufacturer Pharma Health Pakistan (pvt) Ltd, Pinewood Healthcare, Hexpharm, Kimia Farma, Promedrahardjo Farmasi Industri, First Medifarma, Dexa Medica, Novapharin, Jay Formulations Limited
Available Country Pakistan, United Kingdom, United States, Indonesia, India, Nigeria
Last Updated: September 19, 2023 at 7:00 am


Treatment of superficial and deep mycoses:

  • Infections of the skin, hair and nails by dermatophytes and/or yeasts (dermatomycosis, onychomycosis, perionyxis, pityriasis versicolor, chronic mucocutaneous candidiasis etc.) especially when topical treatment is difficult or not very effective, owing to involvement of large skin surfaces or to lesions affecting deeper dermal layers, nails and hairs
  • Yeast infection of the mouth (oral thrush, perleche) and the gastrointestinal tract
  • Vaginal candidiasis, especially chronic recurrent cases or cases responding poorly to topcial treatment
  • Systemic mycotic infections such as systemic candidiasis, paracoccidioidomycosis, histoplasmosis, coccidioidomycosis etc.

Maintenance treatment to prevent recurrence in systemic mycotic infections and in chronic mucocutaneous candidiasis.Prophylactic treatment to prevent mycotic infection in patients with reduced host defenses, e.g., patients with cancer, organ transplant and burns.

Ketoconazole is also used to associated treatment for these conditions: Bacterial Vaginosis (BV), Blastomycosis, Candidiasis, Systemic, Chromomycosis, Chronic Mucocutaneous Candidiasis (CMC), Coccidioidomycosis, Dandruff, Endogenous Cushing's Syndrome, Histoplasmosis, Infections, Fungal, Paracoccidioidomycosis, Seborrheic Dermatitis, Tinea Corporis caused by Epidermophyton floccosumin, Tinea Corporis caused by Trichophyton mentagrophytes, Tinea Corporis caused by Trichophyton rubrum, Tinea Cruris caused by Epidermophyton floccosumin, Tinea Cruris caused by Trichophyton mentagrophytes, Tinea Cruris caused by Trichophyton rubrum, Tinea Pedis caused by Epidermophyton floccosumin, Tinea Pedis caused by Trichophyton mentagrophytes, Tinea Pedis caused by Trichophyton rubrum, Vaginal Candidiasis, Vulvovaginal Candidiasis, Cutaneous candidiasis, Recalcitrant Dermatophytosis, Tinea versicolor caused by Malassezia infection

How Ketoconazole works

Ketoconazole interacts with 14-α-sterol demethylase, a cytochrome P-450 enzyme necessary for the conversion of lanosterol to ergosterol. This results in inhibition of ergosterol synthesis and increased fungal cellular permeability due to reduced amounts of ergosterol present in the fungal cell membrane. This metabolic inhibition also results in accumulation of 14α-methyl-3,6-diol, a toxic metabolite. The increase in membrane fluidity is also thought to produce impairment of membrane-bound enzyme systems as components become less closely packed.


Ketoconazole dosage


Fungal infections:

  • Adult: 200 mg once daily; may increase to 400 mg once daily if clinical response is insufficient. Continue treatment until symptoms have cleared and cultures have become negative.
  • Child: ≥2 yr 3.3-6.6 mg/kg once daily. Treatment duration: 1-2 wk for candidiasis; at least 4 wk in recalcitrant dermatophyte infections and up to 6 mth for other systemic mycoses.
  • Elderly: No dosage adjustment needed.

Topical (Adult)-

Pityriasis versicolor, Skin fungal infections:

  • As 2% cream: Apply 1-2 times daily to cover affected and surrounding area until at least a few days after disappearance of symptoms.
  • As 2% shampoo: Apply on scalp once daily for up to 5 days. For prophylaxis: As 2% shampoo, use once daily for a max of 3 days before exposure to sunlight.

Seborrhoeic dermatitis:

  • As 2% foam: Apply to the affected area bid for 4 wk.
  • As 1 or 2% shampoo: Apply on the scalp twice wkly for 2-4 wk. For prophylaxis: As 2% shampoo, use once every 1-2 wk.

Duration of Treatment

  • Pityriasis versicolor: 1 to 6 weeks
  • Dermatomycoses: 2 to 8 weeks
  • Onychomycoses: 1 to 12 months
  • Mycoses of hair and scalp: 1 to 2 months
  • Chronic mucocutaneous candidiasis : 1 to 12 months
  • Oral mycoses: 5 to 10 days
  • Systemic candidiasis: 1 to 2 months
  • Paracoccidioidomycosis,histoplasmosis
  • and other systemic mycosis: 1 month to 2 years

Side Effects

Ketoconazole is very well tolerated. Nausea and itching may occasionally occur. In some patients, an idosyncratic liver reaction may occur (incidence 1 : 10,000).


Symptoms of overdose include acute liver injury, which may include both hepatocellular and cholestatic injury, accompanied by anorexia, fatigue, nausea, and jaundice. In case of overdose, gastric lavage with activated charcoal may be used if within one hour of ketoconazole ingestion otherwise provide supportive care. If the patient shows signs of adrenal insufficiency, administer 100 mg hydrocortisone once together with saline and glucose infusion and monitor the patient closely. Blood pressure and fluid and electrolyte balance should be monitored over the next few days.


Predisposition to adrenocortical insufficiency. Admin with acidic drink in patients with achlorhydria. Pregnancy and lactation.


Reduced absorption with antimuscarinics, antacids, H2-blockers, PPIs and sucralfate. Reduced plasma concentrations with rifampicin, isoniazid, efavirenz, nevirapine, phenytoin. May also reduce concentrations of isoniazid and rifampicin. May reduce efficacy of oral contraceptives. May increase serum levels of CYP3A4 substrates e.g. digoxin, oral anticoagulants, sildenafil, tacrolimus.

Food Interaction

  • Avoid alcohol. Drinking alcohol while on ketoconazole treatment may cause liver injury.
  • Avoid multivalent ions. They may decrease ketoconazole concentrations.
  • Take with food. Food decreases gastrointestinal irritation caused by ketoconazole.

Ketoconazole Alcohol interaction



Excessive use of alcohol or products containing alcohol together with ketoconazole or levoketoconazole may potentiate the risk of liver injury.

Serious hepatotoxicity has been reported with levoketoconazole.

Fatal hepatotoxicity or requiring liver transplantation have been reported with the use of oral ketoconazole, of which levoketoconazole is an enantiomer.

Some patients had no obvious risk factors for liver disease.

In addition, excessive use of alcohol or products containing alcohol during ketoconazole or levoketoconazole therapy may result in a disulfiram-like reaction in some patients.

Symptoms of disulfiram-like reaction include flushing, rash, peripheral edema, nausea, and headache.

Excessive consumption of alcohol should generally be avoided during ketoconazole or levoketoconazole therapy.

Patients receiving ketoconazole or levoketoconazole should be instructed to contact their doctor immediately if they experience swelling, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, abdominal pain, dark colored urine, light colored stools, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage.

Volume of Distribution

Ketoconazole has an estimated volume of distribution of 25.41 L or 0.36 L/kg. It distributes widely among the tissues, reaching effective concentrations in the skin, tendons, tears, and saliva. Distribution to vaginal tissue produces concentrations 2.4 times lower than plasma. Penetration into the CNS, bone, and seminal fluid are minimal. Ketoconazole has been found to enter the breast milk and cross the placenta in animal studies.

Elimination Route

Ketoconazole requires an acidic environment to become soluble in water. At pH values above 3 it becomes increasingly insoluble with about 10% entering solution in 1 h. At pH less than 3 dissolution is 85% complete in 5 min and entirely complete within 30 min. A single 200 mg oral dose produces a Cmax of 2.5-3 mcg/mL with a Tmax of 1-4 h. Administering ketoconazole with food consistently increases Cmax and delays Tmax but literature is contradictory regarding the effect on AUC, which may experience a small decrease. A bioavailablity of 76% has been reported for ketoconazole.

Half Life

Ketoconazole experiences biphasic elimination with the first phase having a half-life of 2 hours and a terminal half life of 8 hours.


Ketoconazole has an estimated clearance of 8.66 L/h.

Elimination Route

Only 2-4% of the ketoconazole dose is eliminated unchanged in the urine. Over 95% is eliminated through hepatic metabolism.

Pregnancy & Breastfeeding use

Category C: Either studies in animals have revealed adverse effects on the foetus (teratogenic or embryocidal or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the foetus.


Hypersensitivity; preexisting liver disease. Concurrent use with CYP3A4 substrates e.g. HMG-CoA reductase inhibitors (e.g. lovastatin, simvastatin), midazolam, triazolam, cisapride, dofetilide, eplerenone, nisoldipine, pimozide, quinidine, terfenadine, astemizole, ergot alkaloids (e.g. ergotamine, dihydroergotamine).

Special Warning

Renal Impairment: Oral: No dosage adjustment needed.

Hepatic Impairment: Oral: Contraindicated.

Storage Condition

Store between 15-25° C. Protect from moisture and light.

Innovators Monograph

You find simplified version here Ketoconazole

Ketoconazole contains Ketoconazole see full prescribing information from innovator Ketoconazole Monograph, Ketoconazole MSDS, Ketoconazole FDA label


What is Ketoconazole used for?

Ketoconazole is an antifungal medication that is used to treat certain infections caused by fungus. Ketoconazole should be used only when you cannot use other antifungal medications. Ketoconazole applied to the skin it is used for fungal skin infections such as tinea, cutaneous candidiasis, pityriasis versicolor, dandruff, and seborrheic dermatitis.

Is Ketoconazole safe for humans?

Ketoconazole tablets should not be used as a first-line treatment for any fungal infection because it can cause severe liver injury and adrenal gland problems, and advised it can lead to harmful interactions with other medicines.

How does Ketoconazole work?

Ketoconazole works by stopping the growth of the fungus.

What are the common side effects of Ketoconazole?

    Common side effects of Ketoconazole are include:

  • Acne
  • bleeding from sore in the mouth
  • blistering, crusting, irritation, itching, or reddening of the skin
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • cracked, dry, or scaly skin
  • discoloration of the fingernails or toenails
  • dizziness
  • eye dryness, irritation, or swelling
  • red rash with watery, yellow-colored, or pus filled blisters with or without thick yellow to honey-colored crusts
  • skin dryness, pain, rash, redness, or swelling
  • sore in the mouth or on the gums
  • swelling of the face

Is Ketoconazole safe during pregnancy?

There are no controlled data in human pregnancy, limited data indicate no adverse effects of this topical drug on pregnancy or on fetal health. There are no known risks associated with use of Ketoconazole during pregnancy; no effects on the neonate expected. Ketoconazole should be used during pregnancy only if the benefit outweighs the risk to the fetus.

Is Ketoconazole safe during breastfeeding?

Because there is little published experience with Ketoconazole during breastfeeding and its potential liver enzyme inhibition and liver toxicity, other agents may be preferred. However, if oral Ketoconazole is required by the mother, it may not be a reason to discontinue breastfeeding.

Can I drink alcohol with Ketoconazole?

Do not drink any alcoholic beverages during your treatment with Ketoconazole because drinking alcoholic beverages may increase the risk that you will develop liver damage.

Can I drive after taking Ketoconazole?

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you.

When should be taken of Ketoconazole?

Ketoconazole may be taken with or without food, but taking it with food helps to reduce stomach upset. If you are taking an antacid, take Ketoconazole at least 2 hours before or 1 hour after taking the antacid, otherwise Ketoconazole may not be absorbed into the body.

How long does Ketoconazole take to work?

Ketoconazole usually works within 2 to 3 weeks for most fungal infections, but it can take 6 weeks for athlete's foot to get better.

Can Ketoconazole be used long term?

Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered. To do so may cause unwanted side effects or skin irritation.

How long can I take Ketoconazole?

You may need to take Ketoconazole for 6 months or longer to cure your infection completely.

When should not I use Ketoconazole?

Do not use near high heat or open flame, or while smoking.

Can I use too much Ketoconazole?

Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered. To do so may cause unwanted side effects or skin irritation.

Will Ketoconazole affect my fertility?

There's no evidence to suggest that applying Ketoconazole to the skin harms male fertility.

Is Ketoconazole good for face?

You should only apply Ketoconazole cream where your healthcare provider instructs you to. If you need to apply Ketoconazole cream to your face, you can do so, just be careful to avoid getting it in your eyes.

Can Ketoconazole make rash worse?

Ketoconazole strong over the counter steroid creams containing combinations of antifungal and antibacterial medicines can make ringworm worse and cause other health problems.

Does Ketoconazole help with hair loss?

Ketoconazole is also used as a hair loss treatment for androgenetic alopecia in both men and women.

Can topical Ketoconazole damage liver?

Ketoconazole may cause liver damage, sometimes serious enough to require liver transplantation or to cause death. Liver damage may occur in people who do not already have liver disease or any other conditions that increase the risk that they will develop liver damage.

What happens if I miss a dose of Ketoconazole?

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip themissed dose. Take your next dose at the regular time. Do not double the dose to catch up.

*** Taking medicines without doctor's advice can cause long-term problems.