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If you have severe dandruff or seborrheic dermatitis, ketoconazole 2% is a first-line treatment. The approved regimen is simple: apply twice a week for 2 to 4 weeks, leaving it on for 3 to 5 minutes before rinsing. If there is a response, switch to a maintenance regimen of once a week or every 1 to 2 weeks to prevent flare-ups.
Key fact: official information in Spain does not set a timeframe for improvement of "1 to 2 weeks"; it indicates to consult if there is no improvement after 4 weeks.
How many times a week should I use it at first?
Start with two separate applications per week for two to four weeks. This is the recommended dosage in the product information. Some historical sources describe two to three times per week in studies, but three times per week is not an approved dosage; only use it if your doctor recommends it.
Once the itching and flaking are under control, continue with maintenance: once a week or every 1 to 2 weeks, adjusting according to symptoms and season (it usually worsens in winter).
How long should you let it sit before rinsing?
Apply the gel to your scalp and affected areas and leave it on for 3 to 5 minutes. Then rinse thoroughly with water, making sure to wash your skin as well, not just your hair.
Avoid contact with your eyes and don't rub vigorously or use very hot water. If you also have flaking on your eyebrows or nose, follow the instructions given to you by your healthcare professional.
When will I start to see results?
Improvement may be noticeable within the first few weeks, but there's no set timeframe for everyone. If you haven't improved after four weeks, consult a doctor to review your diagnosis.
Keep in mind that you should always check with your doctor or pharmacist before using ketoconazole for your particular case. If you want more details on ketoconazole, consult the patient leaflet Spanish package leaflet.
