Get Your Dog Care Questions Answered by Experts
It sounds like he might be suffering from a bigger problem. Parasites can cause overall bad health in general as can other problems.
He might have an easily treatable condition. You need to make a vet appointment as soon as you can to rule out a bigger problem.
The longer you wait, the worse it could be for the dog.
The puss can come from dehydration and the inability to keep the eyes as moist as it should be. It usually indicates an overall unthrifty feeling of the dog.
The appetite and water consumption low is alarming as well. Your dog is in need of some bloodwork to ensure kidney function is normal and no systemic infections are occurring.
Let me know if you have further questions.DR.V