It's usually caused by an injury, fungal infection, or psoriasis. However, chemicals, certain medications, and serious illness can also make your toenail fall off. Once your toenail falls off, it can't reattach itself and keep growing. You'll need to wait for the new nail to grow back in its place.

Should I be worried if my toenail falls off?

Outcome. While a toenail falling off is usually not a major medical concern, it can be painful and annoying. In some cases, a damaged or detaching toenail may become infected, or it may be a sign of a more serious medical condition.

What illness causes your toenails to fall off?

A nail fungal infection, known as onychomycosis, is one of the most common reasons that toenails detach from the nail bed and fall off.