Thank you for your query at DoctorSpring.com
Looking at your details,it looks that he may be suffering from paronychia .This is nail bed infection.It can be treated by good anti inflammatory analgesic and antibiotic medicines. I will advise him Advil twice daily after food and application of Mupirocin ointment twice daily on the nailbed for 7 days.
Kindly update me after application of the ointment, whether it is getting better.
Hope this will help,