“My prostate has not been found to be enlarged, but I have had years of split stream and slow flow, sometimes only dribbling. After a urinary infection with blood in the urine, I continued to have nighttime frequency. My PSA is described as mid-range. On one bladder-emptying test I voided 168 mL but had 689 mL retained. Rectal examination did not show an enlarged prostate. Supplements have sometimes seemed to help temporarily. I would prefer to avoid invasive procedures. What could be going on?”
Quick Answer
A normal-sized prostate does not rule out a serious urinary-emptying problem.
A reported post-void residual of approximately 689 mL is much more important than whether the prostate feels enlarged on rectal examination. A large residual can occur because of bladder outlet obstruction, urethral narrowing, bladder-neck obstruction, stones, poor bladder-muscle contraction or a combination of these problems.
Because the urinary stream is split, slow and sometimes reduced to dribbling, I would especially want a urologist to exclude a urethral stricture or another structural obstruction.
Saw palmetto, acupuncture or another supplement should not be used as a substitute for establishing why so much urine remains in the bladder.
The 689 mL Residual Is the Key Finding
The most clinically important number in this question is not the PSA.
It is the amount of urine reportedly remaining in the bladder after urination.
A post-void residual, or PVR, measures how much urine remains after you try to empty the bladder.
In this case, the patient reports:
- 168 mL voided
- approximately 689 mL remaining
If those measurements are accurate, this represents very incomplete bladder emptying.
The priority is identifying whether the problem is obstruction, weak bladder contraction or both.
Does 689 mL Mean Chronic Urinary Retention?
It strongly raises that concern, although chronic urinary retention is not diagnosed from one measurement alone.
The American Urological Association has used a post-void residual greater than 300 mL, documented on at least two occasions over six months, as a working definition of non-neurogenic chronic urinary retention.
That threshold is not a magical dividing line, but it shows why a residual approaching 700 mL deserves proper follow-up.
Can You Have Urinary Obstruction Without an Enlarged Prostate?
Absolutely.
BPH is only one possible cause of difficulty urinating.
Other causes include:
- urethral stricture
- scar tissue at the bladder neck
- urinary stones
- prostatitis or urinary infection
- a tight or poorly coordinated pelvic floor
- certain medicines
- neurological disease
- an underactive bladder muscle
This is why persistent lower urinary tract symptoms should not automatically be labeled as enlarged prostate.
What Does a Split Urine Stream Suggest?
A split or spraying urinary stream can have several causes.
One possibility is narrowing somewhere along the urethra.
A urethral stricture can develop after:
- previous urinary procedures
- catheterization
- trauma
- infection or inflammation
- other urethral injury
A stricture can produce a weak, narrow, split or spraying stream and may contribute to incomplete bladder emptying.
Could the Bladder Muscle Be Weak?
Yes.
Sometimes the outlet is not the main problem.
The bladder muscle, called the detrusor, may be unable to contract with enough strength or for long enough to empty the bladder.
This is sometimes called detrusor underactivity or an underactive bladder.
Possible contributing factors include:
- long-standing obstruction
- overstretching of the bladder
- age-related changes
- diabetes
- neurological disease
- previous pelvic surgery or injury
A high residual alone cannot distinguish between obstruction and weak bladder contraction.
Why Can Straining Produce a Bowel Movement?
This is also useful information.
If someone repeatedly bears down strongly to pass urine, the same increase in abdominal pressure can stimulate or assist a bowel movement.
That does not prove the prostate is causing the problem.
In fact, having to strain forcefully to urinate is another reason to determine why the bladder is not emptying normally.
Could Constipation Be Making Urinary Symptoms Worse?
Yes, in some people.
Constipation can contribute to urinary difficulty and may worsen bladder-emptying symptoms.
Regular bowel movements, adequate fiber, appropriate hydration and physical activity are therefore useful general measures.
But constipation would not adequately explain a persistently very large residual without further evaluation.
Does a Normal Rectal Examination Mean the Prostate Is Definitely Normal?
No.
A digital rectal examination gives useful clinical information but does not measure the prostate with perfect accuracy.
Only part of the prostate can be felt through the rectum, and shape and growth pattern vary.
When prostate size matters for treatment decisions, imaging such as ultrasound may provide a better volume estimate.
However, even if imaging confirms a relatively small prostate, urinary obstruction can still exist for reasons unrelated to prostate enlargement.
What Does a “Mid-Range PSA” Mean?
Not very much without the actual number and clinical context.
PSA is a continuous laboratory value rather than simply “good,” “mid-range” or “bad.”
Its interpretation depends on:
- the actual PSA result
- age
- previous PSA measurements
- rate of change
- prostate volume
- recent urinary infection or inflammation
- urinary retention
- recent instrumentation
- medications such as finasteride or dutasteride
- family history and other prostate-cancer risk factors
See my PSA guide for a fuller explanation.
Does Persistent Urinary Retention Mean Prostate Cancer?
No.
The old answer placed too much emphasis on prostate cancer and suggested that biopsy information was essential simply because urinary symptoms continued.
That is not the correct starting point.
Prostate cancer can sometimes coexist with urinary problems, but chronic urinary retention has many benign causes.
PSA, examination, family history and other risk factors determine whether further cancer evaluation is appropriate.
A biopsy is used when the overall cancer assessment provides sufficient reason—not merely because urinary flow is poor.
Could the Previous Urinary Infection Matter?
Yes.
A urinary infection may temporarily worsen frequency, urgency and emptying.
Blood in the urine during an infection can also occur.
However, if blood in the urine recurs after the infection has resolved, or if it persists without infection, that deserves separate evaluation.
Likewise, persistent retention after successful antibiotic treatment suggests that infection was not the whole explanation.
What About Saw Palmetto?
The old answer was too favorable toward saw palmetto and several other herbs.
Some people report symptom improvement, but higher-quality studies have often found that saw palmetto used alone is not more effective than placebo for typical BPH symptoms.
Most importantly, a supplement cannot be assumed to correct a residual approaching 700 mL.
For more detail, see my guide to natural remedies for enlarged prostate.
What About Uva Ursi or Rose Hip?
I would not recommend either product as an established treatment for chronic urinary retention.
A supplement marketed for the urinary tract does not necessarily relieve mechanical obstruction or restore weak bladder-muscle function.
This distinction is especially important when objective testing already shows substantial incomplete emptying.
Could Acupuncture Help?
The old page called acupuncture harmless and suggested that some patients had effectively eliminated their prostate problems with it.
That goes beyond the evidence.
There is limited research suggesting acupuncture might improve some BPH-related symptom scores in the short term, but the evidence is not strong enough to establish it as a treatment for significant bladder outlet obstruction or chronic urinary retention.
What About Commercial “Complete Prostate” Supplements?
I would evaluate the ingredients rather than the marketing claim or the person selling the product.
The old answer criticized one particular supplement because its creator was not a physician. That is not the best scientific argument.
A better question is:
- What exactly is in the product?
- At what dose?
- Has that specific preparation been tested?
- Does it improve meaningful outcomes?
- Does it interact with other medicines?
- Could using it delay treatment of urinary retention?
There is no established “microelement deficiency” that explains ordinary BPH or chronic urinary retention and that can simply be corrected with a prostate supplement.
Would an Alpha-Blocker Help?
Possibly, depending on the cause.
Alpha-blockers relax smooth muscle around the prostate and bladder neck and may improve urine flow in men with lower urinary tract symptoms.
But response to an alpha-blocker does not prove that the prostate is enlarged.
It may also help some forms of functional bladder-outlet resistance.
If significant retention persists despite treatment, further evaluation becomes more important than repeatedly changing medication.
Would Finasteride Make Sense With a Small Prostate?
Not automatically.
Finasteride is generally most useful when prostate enlargement is actually present and the gland is large enough that reducing prostate volume is likely to provide benefit over time.
If prostate size is genuinely small, a urologist may look more carefully for another cause of obstruction before assuming a prostate-shrinking medicine is appropriate.
What Tests Could Help Identify the Cause?
| Test | What it may help determine |
|---|---|
| Repeat post-void residual | Confirms whether a large amount of urine consistently remains after voiding. |
| Uroflowmetry | Measures urinary flow rate and the pattern of the stream. |
| Urinalysis / urine culture | Looks for infection, blood and other abnormalities. |
| Kidney-function tests | May be appropriate when substantial chronic retention is present. |
| Ultrasound | Can assess bladder, residual urine, kidneys and sometimes prostate volume. |
| Cystoscopy | Allows direct inspection for urethral narrowing, bladder-neck obstruction, stones or bladder abnormalities. |
| Urethral imaging | May help define a suspected urethral stricture. |
| Urodynamic testing | Can help distinguish bladder outlet obstruction from weak bladder-muscle contraction when the diagnosis remains uncertain. |
Why Urodynamics May Be Particularly Useful
When the prostate is not clearly enlarged but a patient has severe difficulty emptying the bladder, the key question may be whether the bladder is pushing against resistance or simply cannot contract adequately.
Pressure-flow urodynamic testing can sometimes help separate:
- bladder outlet obstruction
- from detrusor underactivity
This distinction matters because the most appropriate treatment can be very different.
Does a Large Residual Always Mean Surgery?
No.
The old page went too far by saying surgery becomes the only option when medication does not work.
Treatment depends on the cause.
For example:
- a urethral stricture may require specific treatment of the narrowed segment
- a bladder-neck problem may have a different treatment pathway
- a stone may need removal
- an infection requires appropriate antimicrobial treatment
- an underactive bladder may require bladder-management strategies rather than ordinary BPH surgery
- significant prostate obstruction may benefit from a BPH procedure
The diagnosis needs to come before the procedure.
Can Avoiding Invasive Procedures Be Reasonable?
It is understandable to prefer less invasive treatment.
But there is an important difference between avoiding unnecessary procedures and avoiding investigation despite significant retention.
If repeated testing confirms a very large residual, the risks of continued poor emptying have to be weighed against the risks of testing and treatment.
Long-standing urinary retention can be associated with recurrent infections, bladder dysfunction and—in higher-risk situations—upper urinary tract or kidney problems.
What Can Be Done Conservatively While Being Evaluated?
Reasonable measures may include:
- avoiding constipation
- reviewing medicines that can worsen urinary retention
- limiting excessive caffeine and alcohol if they worsen symptoms
- avoiding very large fluid intake at one time
- trying relaxed, unhurried voiding
- in some cases, attempting a second void shortly after the first
These measures may help symptoms but should not be expected to correct severe chronic retention by themselves.
Which Medicines Can Make Retention Worse?
Several common medicines can interfere with bladder emptying in susceptible people.
Examples include some:
- antihistamines
- decongestants
- anticholinergic medicines
- antidepressants
- opioids
- other drugs affecting bladder or urethral function
A full medication review—including over-the-counter cold medicines and supplements—is worthwhile.
When Is Urinary Retention Urgent?
- become completely unable to urinate
- develop severe lower abdominal pain or swelling
- have fever or shaking chills with urinary symptoms
- develop significant visible blood in the urine
- become acutely ill, weak or confused
Acute complete urinary retention requires prompt assessment.
What I Would Ask the Urologist
Given the reported residual volume, I would take the previous test results to a urologist and ask:
- Can the 689 mL post-void residual be repeated and confirmed?
- What is my maximum urinary flow rate?
- Could I have a urethral stricture?
- Could the bladder neck be obstructed even though my prostate is not large?
- Could my bladder muscle be underactive?
- Do I need cystoscopy or urethral imaging?
- Would urodynamic testing help distinguish obstruction from a weak bladder?
- Are my kidneys being affected by the retention?
- What does my actual PSA value mean in context?
- What are the least invasive effective treatment options once the cause is identified?
I would not focus mainly on prostate supplements in this situation. A prostate that does not appear enlarged can still coexist with severe urinary symptoms, and a residual urine volume around 689 mL is significant enough that I would want the cause clearly established. The split stream makes urethral narrowing one possibility, while a weak bladder muscle is another. The most useful next step is a structured urological evaluation of urine flow, repeat residual urine and the urinary outlet rather than assuming either BPH or prostate cancer.