Sodium Bicarbonate Phenol Glycerine Ear Drops which are used to soften dry or hardened earwax. This reduces the need for wax to be physically removed, but also makes ear irrigation easier when removal is necessary. These drops work by stopping the growth of bacteria and fungus. Treating the infection reduces pain and swelling in the ear. Sodium Bicarbonate Phenol Glycerine Ear Drops may be bought over-the-counter or prescribed by your doctor. Use three or four drops twice daily for 3-5 days. Each time you use the drops, allow the solution to remain in your ear for 5-10 minutes.