Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
When we see slow urine flow issues, possibly urinary straining there are several possible causes for this. The top would be a urinary tract infection, bladder/kidney stone (calculi), crystals in his urine, mass in his urinary system or a prostate problem (infection, tumor- he is a bit young for a prostate tumor; and if he is neutered then unlikely to be a prostate problem). Rarely, there can be a more general problem such as kidney issues that could be causing lower than normal urine production, but if this was the case then he should be sick (not eating well, lethargy, possibly vomiting, drinking a lot, etc).
The absolute best step, whether or not you elect to continue with holistic therapies, is to have him get some testing with his veterinarian as soon as you can arrange this to look for some of these problems. The start would be a urinalysis to look for infection/inflammation and crystals. Some imaging of his bladder (ultrasound or X-rays) may be indicated based on this initial test, or more generalized lab work to screen the kidneys and liver (chemistry profile with electrolytes, complete blood count).
There are no easy over-the-counter recommendations I can provide (either for medication or supplements) until we know the cause of his issue. You are welcome to give him a cranberry supplement (such as Cranmate which is made for dogs and chewable) but this only helps support a healthy urinary bladder and is best if used after treatment for the urinary problem.
I am at a point I need to know what questions you have. I hope that the information I provided has been helpful.
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