The possible causes for your cat’s eye staying consistently closed range quite significantly.
The problem could be as simple as a foreign object that has entered the eye, just like what happens to humans.
On the other hand, it could be a sign of a more severe and complicated pause.
Cats like to roam around outdoors and in all sorts of nooks and crannies. Naturally, a foreign object can become lodged in the eye. Like with humans, anything from dust and grass to sand can get in there.
As mentioned previously, cats can get conjunctivitis due to bacterial or viral infections. But they can also suffer from allergies, which may lead to some painful or at least uncomfortable eye conditions.
Keratoconjunctivitis sicca (KCS), or dry eye, is an unfortunate condition where your cat’s eyes are not producing enough tears to clean the eye routinely and naturally.
Glaucoma can happen if an eye infection goes untreated for a while. Some breeds are also more prone to glaucoma. Certain kinds of injury or tumors might inform other causes.