Psoriasis is a chronic autoimmune condition affecting the skin. Signs of psoriasis include skin that is red, thick, scaly, and flaky. About 50% of people who have psoriasis have nail involvement, though fingernails are more often involved than toenails.
Treatment for nail psoriasis usually involves the nail bed that supports the nail or the nail folds that tuck around the edges and may include:
- Treatment applied topically to the nails
- Stronger treatments
- Injections of corticosteroids (or other psoriasis medicines)
- Laser treatment
- PUVA (psoralen plus exposure to UVA rays)
- Systemic treatment for severe psoriasis and nail psoriasis
- Biologics and biosimilars
- Tumor necrosis factor-alpha (TNF-alpha) inhibitors
- Interleukin 12 and 23 (IL-12, IL-23) inhibitors
- Interleukin 17 (IL-17) inhibitors
- Interleukin 23 (IL-23) inhibitors
- T-cell inhibitors
- Methotrexate
- Retinoids
- Cyclosporine
- Apremilast (Otezla)
- Biologics and biosimilars
- Treatment for nail infections
- General nail care
- Keep the nails short
- Protect your nails from damage
- Do not clean underneath the nails with sharp objects or nail brushes; instead, soak affected nails in soapy warm water to remove debris
- Rub moisturizer into the nail and cuticle or soak them in emollient oils
- Soak toenails for at least 10 minutes in a bowl or bath of warm water, to soften the nails before gently filing the thickened part of the toenails with an emery board
- Use good, sharp scissors to trim off small pieces of the nails
- Cut straight across the toenail, to help prevent it from becoming ingrown
- Always wear comfortable shoes with sufficient room for the toes; friction can cause toenail thickening to occur
- Consider buying shoes a size larger than the usual size
What Are Symptoms of Toenail Psoriasis?
Symptoms of toenail psoriasis may include:
- Nail pitting
- White, yellow, or brown discoloration
- Crumbling nails
- Thick nails caused by fungal infection (onychomycosis)
- Nail ridges
- Nail(s) separation from the toe (onycholysis)
- Buildup beneath the nail (subungual hyperkeratosis)
- Blood under the nail
- Nail tenderness
- “Disappearing” nails that can affect a person’s ability to walk
What Causes Toenail Psoriasis?
Toenail psoriasis is caused by the same mechanism that causes psoriasis of the skin: an overactive immune system. The reason the immune system becomes triggered in some people is unknown.
Risk factors that may increase the chances of developing psoriasis include:
- Family history of psoriasis
- Some types of infections, such as strep
- Certain medicines
- Smoking
- Obesity
Triggers for psoriasis flares include:
- Stress
- Skin injury, including scratches, sunburns, bug bites, and vaccinations
- Illness, such as ear infection, bronchitis, tonsillitis, or respiratory infection
- Weather, especially cold weather
- Allergies
- Certain foods
- Alcohol
- Environmental factors
From
https://www.psoriasis.org/
https://www.aad.org/public/diseases/psoriasis/treatment/genitals/nails
https://www.papaa.org/learn-about-psoriasis-and-psoriatic-arthritis/further-resources/nail-psoriasis/