An ingrown toenail occurs when the edge of the nail grows into the surrounding skin. This condition can cause sharp pain, redness, swelling, and sometimes infection. It most commonly affects the big toe but can happen to any toe. Understanding the causes, symptoms, and treatment options is important to manage this condition effectively. What Is an Ingrown Toenail and an Involuted Nail? An ingrown toenail (IGTN) happens when the nail edge pierces the skin. This can feel like