An eye sty is caused by an inflammation in the glands at the eyelash base. It is typically caused by a staphylococcus bacterial infection and may appear on either the inside or the outside of the eyelid. An eye sty may be tender and red, and there may be just one single sty or a group of styes. The sty most likely will drain on its own, but there are things you can do to speed up the healing process. Before attempting to treat your dog for an eye sty, you should be positive that it is just a sty and not something more severe.
Soak a rag or tea bag in warm water, making sure that the water is not too hot.
Hold the rag or tea bag on your dog's eye for five minutes.
Repeat the process a few times a day until the sty comes to a head and the infection drains out.
Clean the area where the infection drains from with warm water several times a day to avoid reinfection of the eyelid gland.
When the sty drains, be sure to keep the eye clean of the infection.
Never try to pop a sty like a pimple. The dog should be diagnosed by a veterinarian because he may be suffering from other conditions such as entropion (rolling in) of the eye or cherry eye, a prolapse of the tear-producing gland.