strain the urine

Straining to Urinate?

The need to strain or push in order to urinate can be due to problems with the contractile force of the bladder or problems with obstruction of the bladder outlet and urethra. Failure to empty due to problems with the contractile force of the bladder may be due to nerve-related disorders such as spinal-cord injury, multiple sclerosis, diabetes, and the like. Failure to empty the bladder due to urethral problems is unusual in women. Some causes of obstruction of the bladder outlet in women include prior vaginal or urethral surgeries, rare strictures of the urethra, and, in rare instances, polyps or cancerous lesions.

Urinary symptoms should always be investigated to rule out some of these unusual but serious conditions. In the urologist’s office, an evaluation for these symptoms would typically include a detailed history, physical examination including a vaginal speculum examination, urinalysis, and an ultrasound measurement of bladder volume after voiding. The most important thing that this latter test would show is whether or not the bladder is completely empty. If the bladder empties completely it makes neurological problems unlikely. If the bladder retains a lot of urine, further studies with urodynamics, a bladder-pressure study that assesses the contractility of the bladder muscle, would be appropriate.

Q2. My husband has been taking oxycodone for pain management for eight weeks now. He is currently having trouble urinating. I understand this is from the medication, but what can he do to overcome the problem? Would drinking more liquid help?

— Irene, North Carolina

Oxycodone, as well as other narcotic pain medications, can lead to bladder problems. Your husband’s difficulty urinating may have resulted because the medication interacts with and blocks some of the nerve signals that cause the bladder to contract. If he cannot be switched to a nonnarcotic pain medicine, then additional evaluation is indicated to assess the severity of his urinary problems. Narcotic pain medicines can also lead to constipation, which, if severe, can prevent normal evacuation of the bladder.

It is important to know whether your husband has an underlying predisposition to bladder difficulties. If he has an enlarged prostate, for example, lower urinary tract symptoms that are caused by prostatic enlargement may be exacerbated by a narcotic pain medication. In such cases, additional medication to treat the underlying lower urinary tract symptoms related to prostatic enlargement might improve his situation. It is unlikely that increasing his fluid intake will resolve bladder-emptying problems — this could actually exacerbate them. Any evaluation of a man who has difficulty urinating would also seek other, less common problems, such as chronic prostatic infection, prostate cancer, bladder stones, and the like.

Learn more in the Everyday Health Pain Management Center.

"I have to push, or strain, in order to urinate. What could be wrong?"

What is the role of urine straining in the emergency treatment of nephrolithiasis?

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Collecting any passed kidney stones is extremely important in the evaluation of a patient with nephrolithiasis for stone-preventive therapy. Yet, in a busy ED, the simple instruction to strain all the urine for stones can be easily overlooked.

Knowing when a stone is going to pass is impossible regardless of its size or location. Even after a stone has passed, residual swelling and spasms can cause continuing discomfort for some time. Be certain that all urine is actually strained for any possible stones. Ideally if patients are seen in the ED, they should be sent home with a strainging device, but in a pinch an aquarium net makes an excellent urinary stone strainer for home use because of its tight nylon weave, convenient handle, and collapsible nature, making it very portable; it easily fits into a pocket or purse.

Related Questions:


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Collecting any passed kidney stones is extremely important in the evaluation of a patient with nephrolithiasis for stone-preventive therapy. Yet, in a busy ED, the simple instruction to strain all the… more