An irritated scalp may cause itching, flakes, redness, greasy scale, crusting or burning. Not every case of “dandruff” is the same.
Possible explanations include seborrhoeic dermatitis, irritation from hair products, contact dermatitis and psoriasis. Fungal infection and other inflammatory conditions can also occur.
Good photographs plus information about products, duration and symptoms can often support an initial assessment.
Pus, severe pain, fever, rapidly increasing inflammation or signs of scarring hair loss are reasons for in-person assessment.
Sometimes the best first step is not adding another product but simplifying the routine and then treating the most likely cause.
Read hair loss.