In short
- Ketoconazole is an antifungal, primarily used for seborrheic dermatitis and dandruff.
- Also has mild anti-androgenic effects on the scalp — relevant to hair loss.
- Nizoral 2% is prescription-only; 1% is over-the-counter.
- Use 2–3 times weekly, left on for 3–5 minutes before rinsing.
Ketoconazole shampoo is quietly the most-recommended shampoo by London trichologists. Beyond its antifungal action against dandruff, it appears to have mild anti-androgenic effects on the scalp — useful in androgenetic hair loss.
The evidence
Multiple small studies show ketoconazole 2% used 2–3 times weekly improves hair diameter and reduces shedding in androgenetic alopecia. The effect is smaller than minoxidil but real, and it stacks well.
How to use it
- Ketoconazole 2% (Nizoral) — prescription in the UK.
- Ketoconazole 1% — over the counter at Boots.
- Wet hair, apply, leave on 3–5 minutes, rinse thoroughly.
- Use 2–3 times per week; alternate with a gentle non-medicated shampoo.
Stacking with other treatments
Compatible with everything — minoxidil, finasteride, PRP, microneedling. Zero drug interactions. Often the third or fourth item in a full London hair loss protocol.
The unglamorous shampoo trichologists actually use.
Frequently asked
Common questions
Can I use ketoconazole daily?+
No — 2–3 times weekly is optimal. Daily use dries the scalp.
Will it lighten dyed hair?+
Slightly, over time. Alternate with a colour-safe shampoo if you're colour-treated.
Is 1% or 2% better?+
2% is more effective; 1% is more accessible. For hair loss, 2% is worth the prescription.
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