Definition: Lichen planus is a skin condition characterized by itchy, flat-topped, purplish bumps that often appear on the wrists, ankles, and lower back.
Causes: The exact cause of lichen planus is unclear, but it is believed to involve immune system dysfunction. It may also be triggered by certain medications.
Symptoms: Symptoms of lichen planus include the development of itchy, polygonal, flat-topped papules or plaques, often with a shiny or scaly appearance.
