How to Treat Bleeding Under the Nail. Bleeding under a fingernail or toenail may mean that you have a nail bed laceration, or it may be hematoma, a bruised nail. If you have hematoma, you can often treat it yourself. If you have a nail bed laceration, however, you need immediate medical attention. There are some steps you should take to determine your best course of action.
Remove any jewelry you may have on and wash the affected area. Apply pressure with a clean cloth to stop the bleeding.
Examine the area. If the finger or toe is bent or deformed, if there is a deep cut, or if part of the nail is lifted away from the nail bed or missing, you need immediate medical attention.
Wrap the hand or foot in a clean towel. Keep it elevated above your heart if possible.
Check your health records to see when you last received a tetanus shot. Then go to a doctor.