This condition typically affects older people. Obviously it differs between races but it seems to start somewhere between ten and twenty years before a person is expected to die of old age.
It begins with ocular migraines; spots or strange lights flickering in your line of sight. These aren't always caused by Clouded Eyes so it's difficult to know whether that is what is going on or not. However, the ocular migraine will increase in frequency from about once a month, to once or several times a week. Then when this has gone on for a couple of months, you start feeling pressure behind the eyes that develops into pain. It is not constant but it is obviously very much a bother. This is followed by blurry vision that rapidly deteriorates as a cloudy film develops over the entirety of your eyes.
If the person is lucky enough to realise what they're experiencing early in the development of the illness, there are treatments that can slow the progress of Clouded Eyes. The more readily available and less expensive treatment is to use a tincture made from boiling special herbs in water, letting it cool and then sifting away the leaves. Then it is dropped onto the eyes twice per day. The second treatment involves magic and has far more costly components. Only the affluent can afford this treatment and it is far more effective in staving off the illness for a much longer time.
Sometimes the ability to see shapes like through a thick fog remains but in most cases it leads to complete blindness.
Though it is far more common for people in the final stages in their life to get Clouded Eyes, it does happen to younger people in very rare cases. Clouded Eyes have been documented as happening to a larger degree in humans, halflings and half-elves but other races can be affected too.