Most people suffer from dandruff at some time in their lives. This can be the result of overusing harsh shampoos and drying hair products. Sometimes, however, dandruff can become severe, and can cause large, oily fakes in the hair. This type of dandruff is usually the result of a more serious scalp condition.
Plaque Psoriasis
Plaque psoriasis affects both the body and the scalp, and causes the skin to overproduce skin cells, resulting in the buildup of scaly plaques. These plaques resemble dandruff, but are much larger, are oily in texture, and are tinged yellow or silver. According to the University of Virgina Health System, if psoriasis plaques are not removed, it can cause the hair follicles on the scalp to become suffocated, and can result in hair loss. Removing the plaques can be painful and difficult without additional treatments. Other treatments entail the application of steroidal cortisone creams and shampoos that contain coal tar, which suppress the overgrowth of skin cells and psoriasis plaques on the scalp. Once the plaques are removed and the scalp is treated, plaque psoriasis can go into remission and the sufferer will no longer have symptoms.
Seborrheic Dermatitis
Seborrheic dermatitis is a condition that causes severe crusting and flaking of the skin. The Penn State Milton S. Hershey Medical Center College of Medicine suggests that seborrheic dermatitis is an inflammatory condition that has a tendency to affect people with a suppressed or stressed immune system, such as people with an autoimmune disease and people with a chronic illness. The flakes associated with seborrheic dermatitis tend to be oily, yellow, and cause the scalp to itch. Seborrheic dermatitis can spread from the scalp onto the ears, face and eyelids. Treatment involves using an extra-strength dandruff shampoo that contains coal tar or zinc, which will improve scalp health and reduce flaking.
Scalp Eczema
When eczema affects the scalp, it causes severe itching and flaking. Scalp eczema usually afflicts infants and toddlers, and is also referred to as cradle cap. The flakes are yellow, dry, and can adhere strongly to the scalp, making it difficult to remove the flakes and to treat the scalp effectively. According to the Penn State Milton S. Hershey Medical Center College of Medicine, scalp eczema might be allergy-related, and can worsen if you're using perfumed shampoos and conditioners. To treat scalp eczema, reduce or eliminate the use of shampoos or conditioners that contain strong chemical ingredients, and apply a natural oil to the head to soften and hydrate the scalp.


