Thanks for the additional information. It is helpful.
It sounds like Charlie has developed a urinary tract infection. Common symptoms of a urinary tract infection are frequent urination, dribbling urine, blood in the urine, squatting frequently to urinate, strong odor to the urine, inappropriate urination and straining to urinate as well as an increase in fluid intake. Uti's can be quite painful which would also explain the panting as well.
A dog with a UTI does not always show all the symptoms and typically displays 2 or 3. I believe you need to have your Vet check your dog out so it can get medication for the problem if your dog is displaying 2 or more of the above symptoms..
Other causes for increased thirst and frequent urination include kidney failure, diabetes mellitus, cushing, and liver disease to name a few. You can read about this here:
Since Cushings also causes increased thirst and urination along with panting, your vet may run additional tests if a uti is not found. Read about cushings here:
The eye is likely to be conjunctivitis, commonly known as pink eye though a scratch might also be to blame.
You can clean the pus off your dog's eye with a warm washcloth. You can also flush your dog's eye with sterile saline solution like contact lens wearer’s use. Your vet will have to be consulted in order to get some medicine for your dog. Frequently an antibiotic eye drop is given for this condition. Sometimes Terramycin Ophthalmic Ointment is used for these problems.
You can read more about canine conjunctivitis here.
Canine conjunctivitis is a common eye problem. It can happen by itself or indicate an underlying problem. Finding the underlying problem can prevent future bouts with conjunctivitis. Underlying conditions that can cause conjunctivitis is KCS (dry eye, insufficient tear production, upper respiratory diseases such as kennel cough. Usually with respiratory infections there will also be coughing, sneezing, nasal discharge, fever, lethargy and loss of appetite. Conjunctivitis can also be cause by a foreign object in the eye or chronic irritation from a development problem of the eyelid and lashes where the lashes rub constantly against the cornea.
You can have your vet check the eye over at the same time as he does the urinalysis. With either condition, I'd suggest a vet visit since you don't want to take a chance with the eyes, but you have to go in for the possible UTI anyway.
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