Psoriasis is a chronic autoimmune condition that accelerates the life cycle of skin cells, causing them to build up rapidly on the skin’s surface. When this condition affects the scalp, it is known as scalp psoriasis. The hair loss is typically temporary and results from intense inflammation and secondary factors associated with managing the condition. Addressing the underlying inflammation and modifying hair care routines are the primary ways to prevent and reverse this hair shedding.
The Direct Connection: Scalp Psoriasis and Hair Loss
The inflammatory activity of psoriasis directly interferes with the natural growth cycle of hair follicles. Chronic inflammation around the hair bulb can weaken the hair shaft and prematurely push the hair from its active growth phase (anagen) into its resting phase (telogen). This disruption can lead to temporary hair shedding called telogen effluvium.
The thick, scaly plaques characteristic of scalp psoriasis physically adhere to hair shafts, cementing them to the scalp. When these scales are shed or removed, the attached hairs are often pulled out along with them. While hair loss from psoriasis is usually temporary, severe or long-standing inflammation can cause irreversible damage. Persistent inflammation or deep scratching can rarely lead to secondary scarring, which permanently damages the hair follicle and prevents future regrowth.
Indirect Factors Causing Hair Shedding
Mechanical trauma is a significant factor in hair loss beyond direct inflammatory damage. The intense itching that often accompanies the condition can lead to aggressive scratching or picking at the scales. This physical manipulation causes breakage of the hair shaft and can dislodge hairs from the follicle.
The psychological impact of living with a chronic condition can also contribute to temporary hair shedding. Increased levels of chronic stress and anxiety can trigger telogen effluvium. Furthermore, efforts to conceal visible plaques, such as using harsh styling products or wearing tight hairstyles, can place excessive tension on the hair follicles, leading to further trauma and breakage.
Psoriasis Treatments That Affect Hair
Certain systemic medications prescribed for moderate to severe psoriasis can cause hair thinning. Methotrexate, a common immunosuppressant, interferes with the rapid cell division necessary for hair growth by targeting fast-growing cells. This effect is dose-dependent, meaning higher doses are more likely to cause noticeable shedding.
Oral retinoids, synthetic forms of Vitamin A used to slow skin cell production, can also be associated with temporary hair loss. Hair loss caused by these systemic treatments is typically reversible, with growth returning to normal once the medication is adjusted or discontinued. Certain topical treatments, like those containing salicylic acid or coal tar, can also cause hair breakage if used too aggressively or if they dry out the hair shaft excessively.
Reversing Hair Loss and Promoting Regrowth
Controlling the underlying inflammation of the scalp psoriasis is key to promoting hair regrowth. Successful treatment of the plaques with topical steroids, Vitamin D analogs, or systemic therapy usually eliminates the inflammatory trigger for hair loss. Once the skin condition is managed, the hair follicles can exit the resting phase and re-enter the active growth cycle.
Gentle hair care is necessary during and after a flare-up to prevent further mechanical damage. This involves avoiding aggressive brushing, minimizing heat styling, and refraining from picking or scratching the scales. Patients can typically expect to see signs of regrowth within a few months after the inflammation has been brought under control.