Nizoral Side Effects
Generic name: ketoconazole
Note: This document contains side effect information about ketoconazole. Some of the dosage forms listed on this page may not apply to the brand name Nizoral.
Some side effects of Nizoral may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.
For the Consumer
Applies to ketoconazole: oral tablet
Get emergency medical help if you have any of these signs of an allergic reaction while taking ketoconazole (the active ingredient contained in Nizoral) hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have any of these serious side effects:
dizziness, fainting, fast or pounding heartbeat;
easy bruising or bleeding, unusual weakness;
numbness or tingly feeling;
severe depression, confusion, or thoughts of hurting yourself; or
nausea, stomach pain, low fever, loss of appetite, weakness, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).
Less serious side effects of ketoconazole may include:
mild nausea, vomiting, or stomach pain;
mild itching or skin rash;
breast swelling; or
impotence or loss of interest in sex.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.
For Healthcare Professionals
Applies to ketoconazole: compounding powder, oral tablet
Ketoconazole inhibits hydroxylation of deoxycortisol, which results in diminished cortisol production, especially when given in divided doses. In some patients, symptomatic adrenal insufficiency may occur, presenting with hyponatremia, hyperkalemia, hypotension, lethargy, depression, and malaise.
Gynecomastia in males results from decreased steroidogenesis and testosterone production, which leads to an increased estrogen to testosterone ratio.
A 77-year-old male with prostate cancer experienced adrenal crisis coincident with ketoconazole (the active ingredient contained in Nizoral) therapy. He presented with progressive right lower extremity weakness, debilitating low back pain, and a serum prostate-specific antigen level of 78.8 ng/mL. He was given ketoconazole 200 mg orally four times daily to reduce serum testosterone levels. Nine days after initiating ketoconazole therapy, he experienced generalized weakness, abdominal pain, nausea with vomiting, and severely diminished mentation. The urology service was advised of the patient's admission and suggested that adrenal insufficiency related to high-dose ketoconazole therapy should be considered in the differential diagnosis. However, a serum cortisol level was not obtained prior to steroid treatment. An ACTH stimulation test performed 2 days later showed no evidence of underlying adrenal insufficiency when the patient was no longer being given ketoconazole.
Endocrine side effects including gynecomastia and breast tenderness have been reported in male patients. Hypoglycemia and hypothyroidism have been reported rarely. Oligospermia has also been reported. Ketoconazole adversely affects the endocrine system through an inhibition of the production of cortisol, which can result in symptomatic adrenal insufficiency. At least one case of adrenal crisis has also been reported.
Gastrointestinal side effects including nausea and vomiting have been reported in 3% to 10% of treated patients. Abdominal pain has been reported in 1.2% of patients. At least 1 case of stomatitis has also been reported.
Gastrointestinal intolerance may resolve with continued therapy and may improve if ketoconazole is taken with food.
Metabolic side effects have included a transient fall in serum cholesterol accompanied by an increase in triglycerides.
Ketoconazole (the active ingredient contained in Nizoral) therapy has commonly been associated with transient elevations in liver enzymes, which have resolved despite continued therapy. However, severe hepatotoxicity (hepatocellular, cholestatic, or mixed) has been reported and generally occurred after one or two months of therapy. Hepatic function usually returned to normal within one month, but cases of hepatic failure and death have occurred. Early signs of hepatotoxicity have included lethargy, dark urine, pale stools, anorexia, malaise, nausea, and jaundice.
Hepatic side effects have been reported. Hepatotoxicity has commonly manifested as transient elevations of liver enzymes but has also, rarely, occurred as hepatitis.
A 72-year-old female with a Candida albicans infection experienced a severe reaction of refractory anaphylactic shock coincident with ketoconazole (the active ingredient contained in Nizoral) therapy. She was initially given oral ketoconazole 200 mg twice daily. She developed hypotension over the first 2 days of treatment (BP 136/82 mm Hg at baseline; 90/50 mm Hg on day 2). Severe hypotension (BP 90/49 mm Hg) unresponsive to fluid therapy or high-dose dopamine developed on day 4 of treatment. When laboratory tests revealed a high level of plasma tryptase, anaphylactic redistribution shock was diagnosed. Her vital signs became more stable after therapy with hydrocortisone and epinephrine infusion.
Hypersensitivity side effects have presented as rash, erythema, and pruritus. Anaphylaxis has been reported. Cross-sensitivity between imidazoles has also been demonstrated.
A 23-year-old female with vaginal discharge experienced fatal aplastic anemia coincident with ketoconazole (the active ingredient contained in Nizoral) therapy. She was admitted with widespread purpuric lesions on her face, arms, and legs. She had taken ketoconazole 200 mg twice daily for vaginal discharge for 4 days before admission. Ketoconazole was discontinued on admission. The patient was diagnosed with aplastic anemia based on clinical findings. The patient did not respond to therapy and died of disseminated candidiasis 2 months later.
Hematologic side effects including hemolytic anemia have been reported rarely. At least one case of aplastic anemia has been reported.
Nervous system side effects including headache, somnolence, dizziness, confusion, and suicidal tendencies have been reported rarely. Paranoid delusions have been reported in a patient treated with ketoconazole (the active ingredient contained in Nizoral) for cutaneous leishmaniasis. At least 1 case of insomnia has also been reported.
Paranoid delusions have been reported in a patient treated with ketoconazole (the active ingredient contained in Nizoral) for cutaneous leishmaniasis.
Dermatologic side effects have been reported. At least five cases of dry skin have been reported, in addition to one case of bruising, six cases of loss of scalp hair, five cases of worsening loss of scalp hair, six cases of desquamation, and three cases of itching.
Genitourinary side effects including at least 13 cases of polymenorrhea anovulatory cycles and 14 cases of anovulatory oligomenorrhea have been reported.
Other side effects including at least 4 cases of fatigue and 3 cases of asthenia have been reported.
More Nizoral resources
Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date, and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This information does not endorse drugs, diagnose patients, or recommend therapy. This drug information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug of drug combination is safe, effective, or appropriate for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of information provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse, or pharmacist.