It is relatively rare for dry ears to become oily ears, because dry ears and oily ears are mainly determined by the body’s genetic makeup, which is inborn and does not change under normal circumstances. The first possibility is that the patient may have purulent otitis media in the ear canal because otitis media secretes a lot of pus, which dilutes the dry earwax into oily cerumen or soft cerumen, which the patient thinks is oily ear but is actually dry cerumen diluted by pus. The second possibility is that some patients have eczema in the external ear canal and there is a large amount of exudate in the ear canal that turns dry cerumen into soft cerumen thinking it is oily cerumen. The third possibility is that some patients also have this condition after water has entered the ear canal. So when dry earwax becomes oily earwax, the patient must go to an outpatient examination to see if there are any other accompanying diseases.