Thumb-sucking may also cause this. One home treatment for fingernail infections is soaking the finger in warm water and a liquid antibacterial soap for 10 minutes three times each day. This will increase the blood supply to the area and help fight the infection. If the infection does not improve after 48 hours of home treatment, you may want to stop by the Student Health Center for further evaluation. Sometimes an oral antibiotic may be necessary in addition to the soaks.
Nervous habits are hard to break.