Thanks for the query. Severe dandruff could indicate dandruff itself which is significant or can indicate beginning of some other skin condition like Seborrheic dermatitis or Scalp psoriasis. Sometimes seborrheic dermatitis co-exists with dandruff and can be determined with more precision during a consultation. A photograph will add in obtaining better recommendations. Kindly consult a dermatologist for exact diagnosis and treatment plan. It is also important to prevent their relapse once you have got it cured.