My 7 year old stallion is having difficulty urinating. He drops, stretches into position, but little urine or nothing comes out. I have only seen this once. He has had an eye infection/irritation for 3 months. We have treated him with most if not all topical eye drops, creams and ointments. When the medicine arrives, I will be treating him with Sulfa-Trim 960 mg (proper body wt dosage) for 10 days & Gentamicin 3mg/ml ointment 3-4x daily for 5 days. Could this be related to the urinary symptoms? He has also been abnormally irritable toward the mare and filly who stay with him in a large pature. He used to let them eat from his pile of food. Now he chases them off until he is done eating unless the feed is more than 100 yds away. Then he chases them between the piles. This behavior is extremely abnormal. Usually you have to check between his legs to make sure he is a stallion. I am so frustrated. This has gone on WAY TO LONG! Any insights would be greatly appreciated.
Teresa

Most likely the Eye and Urinating are not related.
There are many factors to consider.
A vet exam and some bloodwork are your best bet.

The Horse | Male Horse Hygiene
Diseases of the Horse Urinary Organs
Vital sign of the horse

Have you had your vet stain and examine your horses eye? The type of eye medication used can be harmfull if used in the wrong manner. Many eye ointments contain steriods as well as antibiotics, if there is a break on the surface of the cornea steriods can be more harmfull than good. Have you had your stud tested for STD's? There are several that are hard to detect without testing? Have you noticed a difference in the color and smell of his urine? Have you collected some for testing? Early as it is in the year you might not have examined your horses sheath and penis for discharge or even something as simple as a bean? Horses that develop "beans" can feel pain and pressure when they urinate. One early sign of a developing problem with secreations is the stream of urine is often a spray instead of a stream.
Your stallion should be used to having these areas handled and cleaned often, your vet may be able to do an exam and collect samples of any discharge without problem.
A thick, plastic cup, taped to the end of a yardstick is an easy way to collect urine. A yard stick is wide enough to get the tape around the cup and steady on the stick. Turn your stud out for several hours, with a fresh water supply. Provide thick, fluffy bedding, when he first returns to his stall he may urinate, it is a good time to try to collect. Be sure to have a secure top for the cup and try to get the sample to the vet as soon as possible.
It is possible that your horse may be carring some sort of bacterial infection that has been dormant in his system for a while. Saliva, urine, fluid within the eye could carry the bacteria, staph, for example. Be sure to wash your hands and change clothes before you handle other horses. Once the problem or problems are identified and taken care of please let us know what was up. Best of luck to you and your horse. I hope these are minor, unrelated problems that you can quickly get cleared up before breeding season.
Do you do any hand breeding? Do you require mares to be tested for STD's and other infectious conditions. Good luck