2% Shampoo
2% Shampoo
Product Description
Product overview
Nizoral 2% Shampoo is a prescription-strength antifungal treatment shampoo formulated with 2% Ketoconazole — the most potent concentration available for targeting Malassezia fungus, the root cause of dandruff, seborrheic dermatitis, and tinea versicolor. Unlike standard dandruff shampoos that only mask symptoms, Nizoral attacks the fungal overgrowth directly at the source, delivering clinically proven relief from flaking, scaling, and scalp itch.
Targets Fungal Root Cause
Ketoconazole 2% directly disrupts the cell membrane of Malassezia yeast — the primary fungal trigger of dandruff and seborrheic dermatitis — delivering results where zinc pyrithione and selenium sulfide fall short.
Texture & feel
SENSORYTargets Fungal Root Cause
Ketoconazole 2% directly disrupts the cell membrane of Malassezia yeast — the primary fungal trigger of dandruff and seborrheic dermatitis — delivering results where zinc pyrithione and selenium sulfide fall short.
Clinically Proven Efficacy
Multiple peer-reviewed studies confirm ketoconazole shampoo reduces dandruff symptoms in up to 80% of users within 4 weeks of twice-weekly use, outperforming most OTC alternatives in head-to-head trials.
Color & Chemically Treated Safe
The gentle, pH-balanced formula is safe for color-treated, chemically processed, and gray hair when used as directed — two to three times per week or every 3–4 days.
Collagen-Infused Conditioning
Laurdimonium Hydroxypropyl Hydrolyzed Collagen adds a hair-conditioning benefit, helping reduce the drying effect of the cleansing surfactants and leaving strands more manageable post-wash.
Safety & compatibility
SAFEThe FDA label advises consulting a doctor before use during pregnancy or breastfeeding. No adequate controlled studies in pregnant women exist. Topical/scalp ketoconazole is not significantly absorbed into bloodstream, but caution is warranted. Always check with your healthcare provider.
Not considered fungal-acne safe. Contains Coconut Acid, a fatty acid known to feed Malassezia folliculitis. Note: Ketoconazole itself treats fungal acne — but if applying this shampoo to the body for fungal acne treatment, rinse thoroughly and do not leave on skin. As a scalp shampoo used and rinsed, it is generally fine.
Contains Sodium Lauryl Sulfate (SLS), a strong surfactant that can strip scalp moisture and trigger irritation with overuse. Use no more than 2–3 times per week. Discontinue if burning, redness, or scaling worsens.
Safety and effectiveness in children have not been formally established. Use only under dermatologist guidance in pediatric patients.
As a rinse-off scalp shampoo, it does not conflict with topical skincare actives. You can use your usual retinol or exfoliant routine without timing concerns relative to this shampoo.
Avoid contact with eyes. If contact occurs, rinse thoroughly with cold water. Not intended for use near mucous membranes.
Ingredient breakdown
INGREDIENTSKetoconazole 2%Proven
The star active ingredient and only reason this shampoo exists. Ketoconazole is a broad-spectrum synthetic imidazole antifungal that inhibits the synthesis of ergosterol — a critical component of fungal cell membranes. By disrupting ergosterol production, it kills and prevents the overgrowth of Malassezia species responsible for dandruff, seborrheic dermatitis, and tinea versicolor. At 2%, this is the highest concentration available and was originally a prescription-only formulation.
- Mechanism: Inhibits fungal cytochrome P450 enzyme, blocking ergosterol synthesis and causing fungal cell death.
- Clinical evidence: Studies show 2% ketoconazole outperforms selenium sulfide 2.5% in moderate-to-severe dandruff management.
- Anti-inflammatory: Research suggests mild anti-inflammatory action that may benefit scalp redness and irritation beyond antifungal effects.
- Hair growth data: Small studies indicate ketoconazole may reduce scalp DHT activity, offering a secondary benefit for androgenetic alopecia when used alongside minoxidil.
Sodium Lauryl Sulfate (SLS) SurfactantProven
The primary cleansing and foaming surfactant in this formula. SLS is an anionic detergent that efficiently removes sebum, product buildup, and debris from the scalp and hair shaft. It produces the dense, rich lather users notice with Nizoral. While highly effective at cleansing, SLS is the most discussed ingredient for scalp dryness concerns — especially with overuse.
- Function: Primary surfactant — creates foam, disperses oils, and ensures ketoconazole contacts the scalp surface.
- Irritation profile: Studies show prolonged SLS exposure can compromise skin barrier function; at twice-weekly shampoo use, risk is low for most people.
- SLES comparison: Sodium Laureth Sulfate (SLES) is a milder ethoxylated version; this formula uses the stronger SLS variant.
Disodium Lauryl Sulfosuccinate Co-SurfactantProven
A mild co-surfactant that supports SLS in cleansing while helping to moderate its harshness. Disodium Lauryl Sulfosuccinate is considered gentler than SLS and is included here partly as a foam booster and partly as a formulation modifier. It helps improve product texture and spreadability across the scalp.
- Function: Secondary cleansing agent and foam enhancer; described by manufacturers as non-irritating at typical use concentrations.
- Synergy: Works alongside SLS to produce a thorough yet slightly less aggressive cleanse than SLS alone.
Coconut Acid Conditioning AgentPromising
A mixture of fatty acids derived from coconut oil — primarily lauric acid, myristic acid, and caprylic acid. In this formula it serves as a mild emollient and co-surfactant. However, it is the ingredient that makes this formula not fungal-acne safe, as these fatty acids are known to feed Malassezia yeast when applied and left on skin surfaces.
- Composition: Predominantly C12 (lauric acid) and C14 (myristic acid) fatty acids from coconut oil refining.
- Hair benefit: Provides mild slip and conditioning to hair strands, reducing friction and tangling during washing.
- FA concern: Fatty acids in this molecular range are a primary food source for Malassezia folliculitis on skin.
Laurdimonium Hydroxypropyl Hydrolyzed Collagen ConditioningPromising
A quaternized, cationically charged hydrolyzed collagen derivative. This ingredient adsorbs to the negatively charged surface of damaged hair fibers, providing temporary conditioning, improved combing ease, and reduced static. It also claims mild anti-aging and skin-softening properties on the scalp.
- Mechanism: Cationic charge allows bonding to anionic (negatively charged) hair and scalp surfaces, depositing a conditioning film.
- Hair repair: Hydrolyzed collagen peptides temporarily fill in gaps in damaged cuticle layers, improving texture and shine.
- Scalp benefit: Provides a lightweight moisturizing effect to offset the drying action of SLS.
PEG-120 Methyl Glucose Dioleate Thickener / EmulsifierProven
A polyethylene glycol ester of methylglucose dioleate. Primarily functions as a viscosity builder and texture enhancer, giving the shampoo its creamy, thick consistency. It also helps stabilize the emulsion and ensures even distribution of ketoconazole throughout the formula.
- Function: Rheology modifier — controls how the shampoo flows and spreads. Critical for user experience and formula stability.
- Safety: PEG-derived ingredients are generally considered safe in rinse-off formulations at typical concentrations.
Sodium Chloride Viscosity ModifierProven
Common salt. Used universally in shampoo formulations as an inexpensive and effective viscosity modifier. By adjusting ionic concentration, sodium chloride thickens surfactant systems, contributing to the product's desirable consistency without additional synthetic thickeners.
- Function: Controls shampoo viscosity by increasing micelle packing density in surfactant systems.
- Safety: GRAS (Generally Recognized As Safe) ingredient with no safety concerns at cosmetic concentrations.
Imidazolidinyl Urea PreservativeProven
A formaldehyde-releasing preservative that protects the shampoo from microbial contamination and extends shelf life. It is effective against a broad spectrum of bacteria and fungi. While widely used and considered safe at cosmetic concentrations, it is one of the more discussed preservatives for those with chemical sensitivities.
- Function: Antimicrobial preservation — prevents bacterial and mold growth in the water-based formula.
- Concentration: Typically used at 0.1–0.3% in cosmetics — well within safety guidelines set by regulatory bodies.
- Formaldehyde concern: Releases very low levels of formaldehyde over time; considered safe for rinse-off use at regulated levels.
12 ingredients — Active: Ketoconazole 2%. Inactive: Sodium Lauryl Sulfate, Disodium Lauryl Sulfosuccinate, Coconut Acid, Laurdimonium Hydroxypropyl Hydrolyzed Collagen, PEG-120 Methyl Glucose Dioleate, Sodium Chloride, Imidazolidinyl Urea, Sodium Hydroxide, Hydrochloric Acid, Pigment Red 172 Aluminum Lake, Water
Where it fits in your routine
ROUTINEUse 2–3 times per week (not daily). Alternate with a gentle, hydrating shampoo on non-Nizoral wash days to maintain scalp moisture balance.
How to use
HOW TO USEWet Hair & Scalp Thoroughly
Use warm (not hot) water to thoroughly saturate your hair and scalp before applying. Hot water can strip natural scalp oils and worsen dryness.
Apply & Massage In
Apply a generous amount of Nizoral 2% Shampoo directly to the scalp. Work into a rich lather using your fingertips (not fingernails) in gentle circular motions to ensure full scalp coverage.
Leave On for 3–5 Minutes
This contact time is critical — it allows ketoconazole to penetrate and act on the fungal organisms. Do not rinse immediately. Use a shower timer if needed.
Rinse Thoroughly
Rinse completely until water runs clear. Ensure no shampoo residue remains, particularly near the hairline and neck. Avoid contact with eyes during rinsing.
Follow With Conditioner
Apply a moisturizing conditioner to the mid-lengths and ends of hair (avoid the scalp). This offsets the mild drying effect of SLS and keeps hair soft and manageable.
Frequency: 2–3x Per Week
For dandruff and seborrheic dermatitis: use every 3–4 days for up to 8 weeks, or as directed by a dermatologist. For tinea versicolor: a single application is typically sufficient. For maintenance: once weekly or as needed.
Who is it for?
WHOPerfect for you if:
- You have moderate-to-severe dandruff that hasn't responded to zinc pyrithione or selenium sulfide shampoos
- You've been diagnosed with seborrheic dermatitis of the scalp
- You have tinea versicolor on the scalp or body
- You want prescription-strength antifungal action without a doctor's visit
- You have color-treated, gray, or chemically processed hair
- You're using minoxidil or finasteride and want to optimize scalp health
- You experience recurring, persistent scalp itch and flaking
Consider alternatives if:
- You have dry, very porous, or coily/textured hair prone to moisture loss (SLS may worsen dryness)
- You have a known sensitivity to ketoconazole or imidazole antifungals
- You are pregnant or breastfeeding (consult your doctor first)
- You have known formaldehyde sensitivity (contains Imidazolidinyl Urea)
- You want a daily-use shampoo — this is a medicated treatment, not a daily cleanser
- Your dandruff is mild and responds to gentler zinc pyrithione options
- You have bleached or lightened blonde hair (some formulas contain dyes that can discolor)
Scalp type compatibility
SKIN TYPESIdeal for oily scalps with Malassezia overgrowth. Deep-cleansing SLS removes excess sebum while ketoconazole eliminates the fungal driver of flaking.
Use with caution. SLS can strip dry scalps further. Always follow with a hydrating conditioner and limit use to twice weekly. Consider alternating with a sulfate-free shampoo.
Dermatologist-recommended first-line treatment for scalp seborrheic dermatitis. Controls the Malassezia yeast that drives this chronic condition.
SLS is particularly drying on high-porosity coily and curly hair, causing tangling and moisture loss. Use minimally (once weekly), apply conditioner generously, and deep condition after each use.
Nizoral is generally considered safe for color-treated hair. Note: some formula variants contain blue or red dyes. If you have light blonde or bleached hair, check your specific bottle for dye-free labeling.
Results timeline
ONGOING MAINTENANCEImmediate Itch Relief
Most users report noticeable reduction in scalp itch and irritation after the first or second application. The antifungal action begins working during the 3–5 minute contact time, providing rapid symptomatic relief.
~70% noticed improvement in itchingVisible Flake Reduction
Flaking and visible scaling on the scalp and shoulders begins to noticeably decrease. Seborrheic dermatitis patches start to shrink as the Malassezia population is brought under control.
~80% see significant flake reductionSustained Dandruff Control
With consistent twice-weekly use, dandruff and seborrheic dermatitis symptoms are substantially cleared in most users. Scalp redness and inflammation subside. Full treatment course recommended: up to 8 weeks.
~85–90% respond positively to full coursePrevention of Recurrence
Dandruff is a chronic condition. Once cleared, once-weekly or once-every-two-week use helps maintain fungal balance and prevent recurrence. Many users continue long-term use at reduced frequency.
Indefinite use supported by dermatologistsRatings by platform
79K+ REVIEWSPros & cons
BALANCEDPraised
- Fastest-acting dandruff shampoo available OTC — itch relief often after first wash
- 2% ketoconazole is the highest concentration available without a prescription in many countries
- Clinically proven in multiple peer-reviewed studies against Malassezia
- Works on conditions other shampoos fail — seborrheic dermatitis, tinea versicolor
- Suitable for color-treated and chemically processed hair
- Secondary benefit: mild anti-androgenic effect may support scalp health in hair loss treatment regimens
- Only needs to be used 2–3x per week — economical
- Consistently ranked as Amazon's top Beauty & Personal Care product
Criticized
- Contains SLS — can be drying on curly, coily, or already-dry hair types
- Not fungal-acne safe (contains Coconut Acid)
- Some formula versions contain dyes that can discolor bleached or light hair
- Not recommended for daily use — medicated treatment, not everyday shampoo
- Mild medicinal scent that some users find unpleasant
- Pediatric safety not established — not for children without doctor approval
- Pregnancy use requires doctor consultation
- Contains formaldehyde-releasing preservative (Imidazolidinyl Urea) — potential irritant for very sensitive users
Budget-friendly alternatives (dupes)
DUPESSame brand, same antifungal active, but at 1% ketoconazole — half the concentration. OTC without a prescription. Ideal for mild-to-moderate dandruff maintenance, and available in larger sizes. For stubborn or severe dandruff, the 2% strength remains more effective.
Different antifungal mechanism (selenium sulfide vs ketoconazole) but clinically effective for Malassezia-driven dandruff. Studies show ketoconazole is more tolerable and slightly more effective for seborrheic dermatitis. Selsun Blue has a stronger menthol scent and can cause more scalp irritation. Good choice if Nizoral is unavailable.
Widely available and effective for mild-to-moderate dandruff using selenium sulfide. Does not target seborrheic dermatitis as effectively as ketoconazole. Better for everyday dandruff maintenance or mild cases. Available in many hair-type-specific variants including moisturizing formulas for dry hair.
Comparison with competitors
SIDE-BY-SIDESelsun Blue Medicated Max Strength
Storage & shelf life
24 MONTHS24 months after opening when stored correctly. Check the expiry date printed on the bottle — do not use after expiry.
Store at or below 25°C (77°F). Protect from light and freezing. Keep away from direct sunlight and high humidity. Do not store in a hot car or near a heat source.
Opaque flip-cap squeeze bottle. Available in 4 fl oz (118 ml) and 7 fl oz (200 ml) sizes. The opaque bottle protects ketoconazole from light degradation.
The 4 fl oz (118 ml) size is TSA-compliant for carry-on luggage (under 100 ml in the EU). The 7 fl oz size must be checked. Transfer to a travel-size bottle if needed.
Frequently asked questions
FAQThe FDA label advises that Nizoral 2% Shampoo should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus, and recommends consulting a doctor before use while pregnant or breastfeeding. While systemic absorption of ketoconazole from scalp application is very low and generally considered negligible, there are no adequate, well-controlled studies in pregnant women. Caution is exercised because topically applied ketoconazole could potentially be excreted in breast milk at very low levels. Always consult your OB-GYN or healthcare provider before using any medicated shampoo during pregnancy or while nursing.
This requires a nuanced answer. The shampoo is NOT considered fungal-acne safe as a leave-on product because it contains Coconut Acid — fatty acids that feed Malassezia yeast on skin. However, ketoconazole itself is actually a frontline treatment for fungal acne (Malassezia folliculitis) on the scalp. When used as directed — applied, lathered for 3–5 minutes, and rinsed thoroughly — the ketoconazole can treat scalp-based fungal folliculitis. The concern arises if you apply this shampoo to the chest or back for body fungal acne and do not rinse it fully, leaving fatty acids behind. As a properly rinsed scalp treatment, it is generally appropriate for fungal-acne-prone scalps.
Yes, without concerns. Nizoral 2% is a rinse-off scalp treatment, not a leave-on skincare product. It is applied to the scalp, left for 3–5 minutes, and rinsed out — meaning it does not remain in contact with your skin for long enough to interact with your topical actives. You can continue using your retinol, vitamin C serums, or AHA/BHA exfoliants on your face and body as usual. There is no known interaction between ketoconazole shampoo and any topical skincare ingredient when used as directed.
Nizoral 2% is best suited for oily, normal, and combination scalps with active dandruff, seborrheic dermatitis, or tinea versicolor. It works excellently on straight, wavy, and loosely curly hair types. It is less ideal for dry scalps, coily/tightly-curled hair (Type 4), or very porous hair because the SLS in the formula can strip moisture and worsen dryness or tangles. If you have a dry or curly hair type and need ketoconazole treatment, use it minimally (once weekly), apply a deep conditioner after every use, and alternate with a sulfate-free, moisturizing shampoo.
Most users notice a significant reduction in scalp itching after the first 1–2 applications. Visible flaking typically starts reducing within 2 weeks of consistent twice-weekly use. Clinical studies suggest approximately 80% of users with dandruff see meaningful improvement within 4 weeks. For seborrheic dermatitis, a full 4–8 week treatment course is typically recommended. For tinea versicolor, the FDA-approved protocol is a single application — skin may not return to normal color immediately even after the fungus is eliminated, as pigmentation recovers gradually.
Nizoral 2% replaces your regular shampoo on your treatment days (2–3 times per week). Apply to wet hair, lather thoroughly into the scalp, leave on for 3–5 minutes, then rinse completely. Follow with a moisturizing conditioner applied to the mid-lengths and ends. On non-Nizoral days, use your regular shampoo. Do not use Nizoral daily — it is a medicated treatment, not an everyday cleanser. There is no interaction with pre-shampoo treatments, hair masks, or styling products used after washing.
Nizoral 2% Shampoo has a moderate comedogenic rating of 2/5, primarily driven by the Coconut Acid content (a mixture of fatty acids that rate 2–4 on the comedogenic scale). However, as a rinse-off shampoo that is thoroughly washed out after a brief contact time, its comedogenic risk in practice is very low for the scalp and negligible for facial skin (assuming proper rinsing). If you are very acne-prone and apply this shampoo near your hairline or let rinse-water run down your face, rinse carefully. As a properly used scalp shampoo, comedogenic concerns are minimal.
Nizoral 2% Shampoo has a shelf life of 24 months after opening when stored correctly (below 25°C/77°F, away from light and freezing temperatures). Always check the expiry date on the bottle before use. Given that it is used only 2–3 times per week and you typically use a modest amount per application, a 7 fl oz (200 ml) bottle typically lasts 2–4 months with regular use. The 4 fl oz travel size lasts approximately 1–2 months. The opaque bottle design helps protect ketoconazole from photodegradation, preserving potency throughout the product's shelf life.
Verdict: Nizoral 2% Shampoo is the gold-standard over-the-counter antifungal scalp treatment. For anyone dealing with persistent dandruff, seborrheic dermatitis, or tinea versicolor that has not responded to zinc pyrithione or selenium sulfide shampoos, Nizoral 2% delivers prescription-strength results without needing a doctor's visit. Its clinical evidence base is unmatched among OTC shampoos, and its consistent ranking as one of Amazon's top-selling beauty products speaks to its real-world efficacy. The only meaningful limitations are its SLS content (challenging for dry or coily hair types) and the need to pair with a conditioner. Used as directed — twice weekly with adequate leave-on time and thorough rinsing — Nizoral 2% remains the definitive choice for medicated scalp care.
Product Overview
Quick product notes are a great way to check if a product is free from commonly avoided ingredients by skincare enthusiasts. These preferences come about for different reasons depending on the ingredient such as personal experiences, sensitivities, health preferences & etc.
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Quick Product Notes
Ever used a product that promised a certain effect but provided no results? It might not have contained any notable ingredients that could have been responsible for that promised effect. It doesn't matter what the marketing or packaging «promises» it can do, if it doesn't contain anything that can help - then the likelihood of it helping is low.
We help you identify key notable ingredients that have been shown to help with effects such as acne-fighting, brightening, UV-protection, wound healing & anti-aging to help you achieve your skincare goals smarter. Please note that different notable ingredients have varying levels of research behind them, some are extremely well proven yet some have mixed research in their efficacy.
Just because a product doesn't contain any notable ingredients doesn't mean it's bad. And a product with notable ingredients (or even many) doesn't necessarily guarantee the efficacy of the product performing these effects either. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine this.
Be smart and use this as just a starting point for you to make more informed and smarter choices and compare it with reviews to see if the product is right for you
Notable Effects & Ingredients
Why are some products great for some people and horrible for others? Well everyone has different skin types and different reactions to the same ingredients.
We've identified a range of ingredients that are commonly regarded as potentially good or bad for those with Dry, Oily/Acne-Prone or Sensitive skin.
A product that contains good or bad ingredients for your skin type doesn't always flat out make the entire product good or bad for your skin. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine your skins reaction.
One of the best ways to use this section is to troubleshoot products you've had bad experiences with in the past. Check if it contains any of the marked ingredients to point out suspect ingredients to avoid in the future!
Ingredients Related to Skin Types
Ingredient Safety Breakdown refers to the percentage % of ingredients in different risk categories as classified by EWG (Environment Working Group) if they are available. There are almost endless cosmetic ingredients and they are one of the few organisations globally that have assigned ratings to a lot of the more commonly used ingredients which is why we reference them.
EWG is seen by many to be more on the alarmist side in their assignment of health ratings resulting in rating ingredients as riskier than they actually are. We recommend using this a reference point rather than a strict guide of ingredient safety and to always do further research if into ingredients that you may find suspect.
Ingredient Safety Breakdown
Product ingredient list
| EWG | CIR | Ingredient Name & Cosmetic Functions | Notes |
|---|---|---|---|
| 0 |
Ketoconazole
|
|
|
| 0 |
Sodium Lauryl Sulfate
|
|
|
| 1 |
Disodium Lauryl Sulfosuccinate
Skin Conditioning, Hydrotrope, Sufactant, Foam Boosting, Foaming
|
|
|
| 0 |
Coconut Acid
Cleansing, Emollient, Emulsifying
|
|
|
| 0 |
Laurdimonium Hydroxypropyl Hydrolyzed Collagen
Skin Conditioning
|
|





