Nocturia: waking at night to pass urine, causes and treatment

Oxford Health NHS Foundation Trust says nocturia is the medical term for waking up at night to pass urine, and that it is normal for adults to wake once a night to urinate. The Bladder and Bowel Community says it can be quite normal to wake once or twice during the night, and that if you have to do so more often, it can become annoying and tiring.

Although nocturia may be associated with ageing, the Bladder and Bowel Community says it might be caused by a medical problem that can be treated, so it is a good idea to report it to your doctor, continence nurse or specialist physiotherapist, particularly if it has come on quite quickly and recently.

Oxford Health says that after assessment the cause is usually one, or a combination, of three patterns.

The Bladder and Bowel Community says nocturia can be caused by medical conditions that have nothing to do with age. It also lists three common causes: fluid management, neurological diseases that affect bladder control, and urinary tract or bladder infections.

• Diabetes, which can lead to bladder problems (Bladder and Bowel Community).

• Kidney stones, a urinary tract or bladder infection, or an overactive bladder (Bladder and Bowel Community).

• Pregnancy, as the growing baby increases pressure on the bladder (Bladder and Bowel Community).

• A heart condition, which can weaken the circulatory system (Bladder and Bowel Community).

• Some medicines; NICE CKS names diuretics and antimuscarinics among drugs that can contribute to urinary symptoms in men. Do not stop a medicine unless advised.

• Constipation, which can press on the bladder, and excessive fluid intake (Bladder and Bowel Community).

• In men, benign prostatic enlargement is a common cause of lower urinary tract symptoms (NICE CKS).

The Bladder and Bowel Community gives several reasons. The body makes a hormone at night that slows kidney function, but as you age less may be produced, so the bladder continues to fill at its daytime rate. Later in life the heart and circulation may be less efficient, so fluid collects around the ankles during the day and is reabsorbed and filtered when you lie down. The bladder also loses elasticity.

For men, it says the prostate gland becomes enlarged in almost all men as they get older, which can restrict the bladder outlet so that the bladder does not empty completely and fills again more quickly. It says this is not the same as prostate cancer.

Oxford Health says a continence assessment could include a detailed history of urinary symptoms, a urine test to rule out infection, a bladder scan to check the bladder empties properly, and a bladder diary to monitor fluid intake and urination patterns.

The Bladder and Bowel Community adds blood tests (which may include kidney function, HbA1c or glucose and calcium), an ultrasound scan if blood tests are abnormal, and polysomnography if obstructive sleep apnoea is suspected. It suggests keeping a record of bladder activity for at least 3 days before the appointment. NICE CKS says men with bothersome urinary symptoms should be asked to complete a urinary frequency-volume chart for at least 3 days, with a urine dipstick test and sometimes kidney function tests and PSA.

Oxford Health says that once the cause is identified, different strategies help depending on the pattern. It advises always consulting your healthcare provider before changing medication.

NICE CKS says lower urinary tract symptoms in men are grouped into storage symptoms (urgency, daytime frequency, nocturia and incontinence), voiding symptoms and post-micturition symptoms. Management includes excluding serious causes, tailored advice, and drug treatment if conservative management is unsuccessful: an alpha-blocker for moderate to severe symptoms, a 5-alpha reductase inhibitor for larger prostates, an antimuscarinic or mirabegron or vibegron for overactive bladder symptoms, and a loop diuretic or oral desmopressin for men with nocturnal polyuria.

The Bladder and Bowel Community lists pregnancy as a cause, because as the baby grows inside the womb the pressure on your bladder increases so that it is not able to hold as much urine as usual. If nocturia comes with pain on passing urine, tell your midwife or GP, as infection needs to be ruled out.

The Bladder and Bowel Community says to make an appointment with your doctor, continence nurse or specialist physiotherapist if the problem is starting to affect your day-to-day life, and that it is best to seek medical advice, particularly if it has come on quite quickly. NICE CKS says serious causes of urinary symptoms should be excluded. The Bladder and Bowel Community also lists pain or discomfort when you pass urine among the questions a clinician may ask, so mention it.

On the NHS, continence assessment can be through a GP, a community bladder and bowel service or a continence nurse, and some services accept self-referral. Private urology or continence assessment is available for quicker access, and the same assessment steps and treatments apply. Ask for results to be shared with your GP.