NIZORAL ANTI-DANDRUFF

Clinical safety rating: caution

Comprehensive clinical and safety monograph for NIZORAL ANTI-DANDRUFF (NIZORAL ANTI-DANDRUFF).

How it works

Ketoconazole, an imidazole antifungal agent, inhibits fungal cytochrome P450 14α-demethylase (CYP51), preventing the conversion of lanosterol to ergosterol, an essential component of fungal cell membranes. This disrupts membrane integrity and function.

What the body does with it

Metabolism	Topical application yields minimal systemic absorption; metabolism via hepatic CYP3A4 if absorbed; primarily excreted unchanged in feces.
Excretion	Primarily fecal (57%) via biliary excretion as unchanged drug and metabolites; renal excretion accounts for approximately 13% (2-4% unchanged).
Half-life	Terminal elimination half-life is biphasic: initial 2 hours, terminal 8 hours (range 6-10 hours). After topical application, systemic absorption is minimal, resulting in an effective half-life of 72-96 hours in skin.
Protein binding	99% bound to plasma proteins (primarily albumin).
Volume of Distribution	Vd/F (apparent) is approximately 2.5-3.1 L/kg, indicating extensive tissue distribution. For topical use, systemic Vd is not clinically relevant due to minimal absorption.
Bioavailability	Topical: Systemic absorption <1% of applied dose. Oral (tablet): Bioavailability is dose-dependent and variable (mean ~75% in fasting state, increased with acidic pH and food).
Onset of Action	Topical: Relief of itching and scaling begins within 2-3 days of daily use; significant reduction in dandruff severity after 1-2 weeks. Oral (systemic use): Onset of antifungal effect within 24-48 hours.
Duration of Action	Topical: Effects persist for 7-10 days after discontinuation; regular use (twice weekly) maintains control. Oral: Duration varies with indication; for systemic mycoses, treatment typically continues for weeks.

Classification & Brands

Dosing & administration

Apply to wet hair, lather, and leave on for 3-5 minutes before rinsing. Use twice weekly for 4 weeks, then as needed to control dandruff.

Dosage form	SHAMPOO
Renal impairment	No dosage adjustment necessary for topical use. No data for systemic exposure.
Liver impairment	No dosage adjustment necessary for topical use. No data for systemic exposure.
Pediatric use	Safety and effectiveness in children <12 years not established. For children ≥12 years, use same as adult.
Geriatric use	No specific dosage adjustment required; use with caution if skin barrier compromised.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for NIZORAL ANTI-DANDRUFF (NIZORAL ANTI-DANDRUFF).

Breastfeeding	Excretion into breast milk is unknown for topical ketoconazole; however, systemic absorption is minimal (<1%). The M/P ratio is not established. Use with caution; benefit likely outweighs risk for anti-dandruff treatment.
Teratogenic Risk	Ketoconazole topical (Nizoral Anti-Dandruff) is considered low risk for teratogenicity due to minimal systemic absorption. No specific fetal risks identified in the first trimester; however, systemic ketoconazole is teratogenic in animals and can cause fetal harm if absorbed significantly. For topical use, risk is negligible.

Warnings & precautions

■ FDA Black Box Warning

None

Side Effect Profile

Serious Effects

Absolute Contraindications

["Hypersensitivity to ketoconazole or any component of the formulation.","Do not use on broken or inflamed skin (relative contraindication)."]

Clinical Precautions

Precautions

["For external use only; avoid contact with eyes, mucous membranes, and broken skin.","Discontinue if irritation or sensitization occurs.","Do not use occlusive dressings unless directed.","Use caution in patients with known hypersensitivity to imidazole antifungals."]

Clinical Tips & Counseling

Drug interactions

Loading safety data…

NIZORAL ANTI-DANDRUFF

Clinical safety rating: caution

Comprehensive clinical and safety monograph for NIZORAL ANTI-DANDRUFF (NIZORAL ANTI-DANDRUFF).

How it works

What the body does with it

Metabolism	Topical application yields minimal systemic absorption; metabolism via hepatic CYP3A4 if absorbed; primarily excreted unchanged in feces.
Excretion	Primarily fecal (57%) via biliary excretion as unchanged drug and metabolites; renal excretion accounts for approximately 13% (2-4% unchanged).
Half-life	Terminal elimination half-life is biphasic: initial 2 hours, terminal 8 hours (range 6-10 hours). After topical application, systemic absorption is minimal, resulting in an effective half-life of 72-96 hours in skin.
Protein binding	99% bound to plasma proteins (primarily albumin).
Volume of Distribution	Vd/F (apparent) is approximately 2.5-3.1 L/kg, indicating extensive tissue distribution. For topical use, systemic Vd is not clinically relevant due to minimal absorption.
Bioavailability	Topical: Systemic absorption <1% of applied dose. Oral (tablet): Bioavailability is dose-dependent and variable (mean ~75% in fasting state, increased with acidic pH and food).
Onset of Action	Topical: Relief of itching and scaling begins within 2-3 days of daily use; significant reduction in dandruff severity after 1-2 weeks. Oral (systemic use): Onset of antifungal effect within 24-48 hours.
Duration of Action	Topical: Effects persist for 7-10 days after discontinuation; regular use (twice weekly) maintains control. Oral: Duration varies with indication; for systemic mycoses, treatment typically continues for weeks.

Classification & Brands

Dosing & administration

Apply to wet hair, lather, and leave on for 3-5 minutes before rinsing. Use twice weekly for 4 weeks, then as needed to control dandruff.

Dosage form	SHAMPOO
Renal impairment	No dosage adjustment necessary for topical use. No data for systemic exposure.
Liver impairment	No dosage adjustment necessary for topical use. No data for systemic exposure.
Pediatric use	Safety and effectiveness in children <12 years not established. For children ≥12 years, use same as adult.
Geriatric use	No specific dosage adjustment required; use with caution if skin barrier compromised.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for NIZORAL ANTI-DANDRUFF (NIZORAL ANTI-DANDRUFF).

Breastfeeding	Excretion into breast milk is unknown for topical ketoconazole; however, systemic absorption is minimal (<1%). The M/P ratio is not established. Use with caution; benefit likely outweighs risk for anti-dandruff treatment.
Teratogenic Risk	Ketoconazole topical (Nizoral Anti-Dandruff) is considered low risk for teratogenicity due to minimal systemic absorption. No specific fetal risks identified in the first trimester; however, systemic ketoconazole is teratogenic in animals and can cause fetal harm if absorbed significantly. For topical use, risk is negligible.

Warnings & precautions

■ FDA Black Box Warning

None

Side Effect Profile

Serious Effects

Absolute Contraindications

["Hypersensitivity to ketoconazole or any component of the formulation.","Do not use on broken or inflamed skin (relative contraindication)."]