Psoriasis of the scalp is a long-term skin condition that may involve intermittent flareups followed by periods of time when your symptoms subside. Symptoms of psoriasis on your scalp may include itching, cracking and bleeding of your skin and thinning of your hair in affected areas. According to the Mayo Clinic and the American Academy of Dermatology, causes of psoriasis on your scalp include stress and infections.
If you get an infection such as strep throat or a yeast infection, these conditions can cause your immune system to become overactive and trigger your scalp psoriasis.
Injuries to your scalp may cause psoriasis, including the use of chemicals to color, relax or curl your hair; insect bites or stings, or sores and other wounds.
If you take medications including retinoids for acne, iodides for thyroid disorders, or lithium for psychiatric disorders, these may cause scalp psoriasis to flare up.
If you partake in certain personal habits such as drinking alcohol or smoking tobacco, these substances can act as toxins that trigger flareups of psoriasis.
Scalp psoriasis may be triggered by experiencing an unusual amount of emotional or physical stress in your life, such as loss of your job or arguments with your partner.
Exposure to extreme weather, especially very cold weather, as well as getting a sunburn on your scalp may trigger your psoriasis to flare up.