The most common causes of infection are piercing the ears with unsterile equipment, inserting unsterile posts, or frequently touching the earlobes with dirty hands. Tight earrings don't allow air to enter the channel through the earlobe. Also, the pressure from tight earrings reduces blood flow to the earlobe and makes it more vulnerable to infection. Some inexpensive earrings have rough areas on the posts that scratch the channel and can result in infection. Inserting the post at the wrong angle also can scratch the channel, so a mirror should be used until insertion becomes second nature.
Posts containing nickel can also cause an itchy, allergic reaction.
With proper care, most mild earlobe infections will clear up in 1 to 2 weeks. Recurrences are common if you are not conscientious in ear and earring care. Cleanse them with rubbing alcohol. Clean both sides of the earlobe with rubbing alcohol. Continue the antibiotic ointment for 2 days beyond the time the infection seems cleared.