Otitis externa can be extremely painful, where swelling of the ear canal skin closes up the canal itself. The ear gets very tender, there may be a discharge and it feels blocked.
Treatment consists of cleaning the ear, usually by suction and placing ear dressings which soothe the skin and reduce swelling. Oral and topical antibiotics are often used in this condition, which takes at least around 3 days for the pain to subside, even if treated properly.
Otitis externa may become more aggressive in diabetics, who may need closer attention.
References
Agius AM, Pickles JM, Burch KL. A Prospective Study of Otitis Externa. Clin. Otolaryngol. 1992, 17, 150-154.
Agius AM, Reid AP, Hamilton C. Compliance with Short Term Topical Aural Antibiotic Therapy. Clin. Otolaryngol. 1994, 19, 138 - 141