ALOPECIA AREATA AND PSORIASIS
The causes of alopecia areata and psoriasis are very similar; both are autoimmune conditions, meaning a group of white blood cells attacks cells in the skin or hair.
People who experience alopecia areata or psoriasis have a genetic predisposition. However, the onset of both conditions still requires a trigger in the form of a viral or bacterial infection, a vaccination, stress, trauma to the skin or exposure to a novel substance.
Stress can exacerbate both conditions through its impact on the sympathetic nervous system. Stress causes sympathetic nerves to increase their production of noradrenaline in the skin, intensifying the autoimmune reaction.
FOLLICULITIS DECALVANS AND LICHEN PLANOPILARIS
Folliculitis involves inflammation of the hair follicles, while decalvans is the Latin term meaning “to cause baldness”. Folliculitis decalvans is therefore the baldness associated with folliculitis. It is a slowly spreading inflammatory condition whereby destruction of the hair follicles gives rise to round or oval patches of permanent baldness.
Lichen is the name for a specific type of skin lesion, which appears as a solid papule. Lichenization describes the development of those lesions on the skin. Lichen planus is a general term describing the eruptions of lichen on the surface (plane) of the skin.
HAIR THINNING IN MEN & WOMEN
This condition is characterized by the hair thinning out along the front and/or top area of the scalp. It is thought to be inherited from both sides of the family, meaning two parents with thick hair can share a daughter who experiences hair thinning. Sometimes associated with increased oiliness of the skin, excessive facial hair and a sensitive, "burning" scalp.
Estrogens (female hormones) are "good" for the hair, while androgens (male hormones) are "bad" for the hair. Men and women produce both types of hormones. Women with genetic thinning typically have normal androgen levels. It is a sensitivity to the dihydrotestosterone (DHT) produced by testosterone in the skin that adversely affects the hair.
Seborrheic dermatitis is a common skin condition that causes scaly patches, red skin and stubborn dandruff. It primarily affects the scalp but can also be found in oily areas of the body, such as the face, sides of the nose, eyebrows, ears, eyelids and chest. Seborrheic dermatitis is also called dandruff, seborrheic eczema and seborrheic psoriasis.
The sign and symptoms of seborrheic dermatitis may include: skin flakes (dandruff) on your scalp, hair, eyebrows, beard or mustache; patches of greasy skin covered with flaky white or yellow scales or crust on the scalp, face, sides of the nose, eyebrows, ears, eyelids, chest, armpits, groin area or under the breasts.
The signs and symptoms may become more severe when you're stressed, and they tend to flare in cold dry weather.