A fingernail may detach from its nail bed due to an injury, fungal infection, skin condition, chemicals or medications, according to WebMD. Severe illnesses may also cause fingernails to detach. The technical name for the condition is onycholysis, notes MedicineNet.
Injuries to fingernails most commonly occur in people who have long fingernails that get jammed or hit. The fingernail may pry away from the nail bed and eventually fall off after suffering the trauma. Fungal nail infections swarm underneath the nail and cause it to detach. Symptoms of a fungal infection of fingernails include nails that appear yellow, cracked, streaked, thickened or spotted, states WebMD. Psoriasis is a skin condition that may cause a fingernail to fall off, and acetone nail polish may cause the same condition. One possible side effect of chemotherapy is detached fingernails.
When a fingernail falls off, it cannot be reattached. An entire fingernail takes up to six months to grow back to its normal length. Patients should remove the nail, keep the area dry to prevent infection and wait for the new nail to grow back, explains WebMD. Tips to aid healing include covering the affected nail with tape or an adhesive bandage to protect the growth; trimming a partially detached nail to prevent further damage from catching and tearing; and covering the fingernail with an antibiotic ointment to keep out infections.