Ear infections are infections that develop in the inner ear from sinus drainage and fluid build up. Symptoms of an infection can be fever, ear pain and dizziness. More extreme symptoms can include nausea and loss of hearing. Ear infections tend to be more prevalent in children where ears are not as developed and fluid can get trapped easily.
Ear infections can last anywhere from a couple of days to a week or so depending on how fast the infection was caught by a doctor and what treatment was used. Antibiotics can help speed the healing process if it is a bacterial infection, however if it is viral, then this approach won't help. Also antibiotics won't remove the inner ear fluid. Drying drops can help with that, but it is sometimes painful. Viral ear infections tend to last longer since the virus has to run its course. The only thing that can be done is to treat the symptoms to give the patient some comfort.
An ear infection that is left completely untreated can heal itself in time, however it can cause damage to hearing. This is because ear infections cause pressure on the ear drum. The pressure can sometimes build to a point that the ear drum can burst. This will, at the very least, cause a temporary loss of hearing and sometimes a permanent one. If the ear drum bursts, it can take several weeks for the ear to heal, but the pain from the ear infection usually subsides somewhat because the fluid is released.