The frequency of hair washing for those with dandruff depends on the severity and underlying cause. Generally, it’s recommended to wash hair every 2-3 days or more frequently if needed. Use a gentle, dandruff-specific shampoo that contains medicated ingredients like selenium sulfide, zinc pyrithione, or ketoconazole to help control fungal overgrowth and scalp inflammation. Massage the shampoo into the scalp thoroughly and leave it on for a few minutes before rinsing. Avoid harsh products, excessive heat styling, and tight hairstyles that can worsen dandruff. Consult a dermatologist if over-the-counter treatments are ineffective.