What should you know about thick brittle yellow toenails?

Fungal nail disease can make the nail thicker, discoloured, crumbly, or separated from the nail bed. Nail psoriasis may cause pits, ridges, lifting, or yellow-brown patches, sometimes alongside psoriasis elsewhere. Tight footwear, repeated impact, or an old toe injury can also alter nail growth. The appearance alone cannot confirm the cause, and more than one problem may be present.

Keep the feet clean and dry, change socks when damp, and choose shoes with room around the toes. Trim nails straight across without digging into the corners, and do not share clippers. Avoid scraping under the nail or applying leftover prescription medicine. A clinician may inspect the nail and take a small sample before recommending treatment. Read about Nail Fungus and Nail Psoriasis for conditions that can resemble this pattern.

Arrange a dermatology assessment if the change persists, spreads to other nails, or makes walking uncomfortable. Seek prompt medical care for increasing redness, warmth, swelling, drainage, marked pain, or a dark streak that is new or changing. People with diabetes, reduced circulation, reduced sensation, or a weakened immune system should arrange assessment sooner after any foot or nail problem.

Could this be fungal infection, psoriasis, or damage from footwear? Is a nail sample needed before treatment? Which options fit my medicines and health conditions, including Oral Antifungal Treatment or Laser Treatment For Nail Fungus?