Deafness, or hearing loss, is a common symptom and can be reversible to a degree in most cases. It may come on slowly over many months or years, but in other situations there may be a sudden loss of hearing. It may be one-sided or in both ears.
You may notice you cannot hear what people are saying and have to ask them to repeat themselves. You may notice you need to be able to see their face in order to try to read their lips, particularly in a busy room with a lot of background noise. Sometimes other people notice your hearing loss before you do, passing comment that you seem to have the TV or radio up louder than is comfortable for them. Some types of hearing loss are accompanied by pain, some not.
There are many causes of hearing loss. They are divided into conductive (caused by a blockage of the sound waves through the outer or middle ear) or sensorineural (caused by damage to the inner ear or nerves transmitting to the brain). Deafness can also be a mixture of the two types.
Conductive causes are ear wax, external ear infections, middle ear infections, foreign body in the ear (mostly in children), perforated ear drum, or eustachian tube dysfunction. These causes tend to show themselves quite promptly.
Sensorineural causes account for 90% of hearing loss and tend to develop more gradually. Causes are trauma such as working in extremely loud workplaces, without ear protection, listening to very loud music for long periods, or simply old age.
The type of hearing loss is frequently obvious as first presentation to a doctor who may see infection in the outer or middle ear or a perforation of the ear drum. However there are further tests that can be done particularly pure tone audiometry. This is the definitive test to determine the type and the degree of deafness.
Infections can be treated with antibiotics, perforated ear drums frequently mend themselves or may require surgery. Eustachian tube dysfunction (catarrh in the tube from the ear to the throat internally) can be treated with very low-dose steroid nasal sprays, but can take some weeks to improve. Age-related deafness is of the sensorineural type and is caused by the general effects of time on the body and requires a hearing aid. Many hearing aids now are very small and hardly noticeable to other people. Surgery can be used to implant hearing devices in some cases.