Suggest Treatment For Inflamation On Finger Nail

I have had inflamation on my left middle finger just under the nail for about 3 months. The nail is now growing out with a ridge in it. What do you recommend? I am 63 years old. 175 lbs. Had a similar issue several years ago with the index finger on my left hand bit it was just swolen and that finger has become slightly deformed, but the nail is ok.