10/10/2024
TLDR: Apparently, prednisone can cause male dogs to be unable to urinate in rare cases.
Full story:
While I was in Germany, Theo had a bad breakout on his head and Mark brought him to the Dr. Lovell. Dr. Lovell prescribed antibiotics and prednisone. By 11 PM that night, Mark knew something was wrong. Theo was straining to p*e, only a couple of drops were coming out, and the dog looked like he swallowed a watermelon.
Off the the emergency vet. Catheterized Theo and drained an enormous amount of urine.
First suspicion was bladder stones. X-ray was negative for bladder stones.
Emergency vet suggested it was probably benign prostatitis. Suggested neutering would resolve the problem. Recommended following up with Dr. Lovell in the morning.
Next morning, Mark took Theo to Dr. Lovell. Bladder distended again, dog still unable to urinate. Dr. Lovell drained the bladder and examined the prostate and said the prostate was within normal for a Bull Terrier. Dr. Lovell said that both he and his wife (who is also a vet) have seen rare cases where prednisone can cause this to happen and that would be his suspicion in this case.
So they took Theo off prednisone, kept him for the day and drained his bladder. We had to have the bladder drained one more time the next morning but by that afternoon it was completely resolved. It took about 36 hours of being off the prednisone to resolve completely.
Just something to keep in mind...if your male dog is on prednisone and he suddenly can't p*e, it's a true medical emergency and you can't just stop the prednisone and hope it gets better. You still should immediately bring him to the vet and check for stones and have his prostate examined to rule out benign prostatitis (or prostate cancer), but you might also consider cutting out the prednisone to see if that is the culprit.
