Even without therapy, middle ear infections frequently resolve on their own within 2 or 3 days. In certain circumstances, even after antibiotic therapy, an infection might remain longer (with fluid in the middle ear for 6 weeks or more). But most cases resolve within 10 to 14 days. The reason that they tend to go away on their own is because the bacteria that cause them produce toxins that irritate and damage the middle ear. So even though we can't see them, there are always many bacteria in the middle ear with the potential to cause further problems if they are not treated promptly. However, this doesn't mean that you shouldn't see your doctor if you have persistent symptoms. Some people do require additional treatment -- such as another course of antibiotics or steroid drops to dry out the ear -- before their symptoms improve.