Squinty Eyes
This is a common problem when shampoo or other irritants get into a dog's eyes. Sometimes loose hair from the haircut can get in there as well. You know that feeling when an eyelash gets into your eye — you squint, tear up, and rub your eye.
Flush It Out
The best thing to do with any eye irritation is to flush that eye with water for a few minutes. Hold the eye open as best you can and run cool water on low pressure all along the eye. It should flush all the irritants out. If you've used mineral oil in the eyes to protect them and a degreasing shampoo got into the eye, you really need to be diligent about flushing the eye.
Mineral oil eye protection drops may be a good idea to protect eyes from shampoo irritation, but certain shampoos can break down the oil and get under it. It's easier to flush out shampoo from a dog's eye than it is to treat a corneal abrasion caused by using eye protection drops with the wrong shampoo.
If, after flushing the eye for several minutes, the dog is still rubbing his eye and squinting, it's time to see a vet. Most corneal abrasions heal quickly with the correct treatment.
