Differentiating the causes of nocturia

Nocturnal polyuria (NP) is a common underlying condition of nocturia1

Nocturia has been traditionally regarded by urologists as a urine storage symptom associated with benign prostatic hyperplasia (BPH) and/or overactive bladder (OAB).1 BPH can result in bladder outlet obstruction (BOO) causing nocturia symptoms.1 Studies show that NP presents in 76–88% of reported nocturia cases – the majority of patients suffering from nocturia.1 More importantly, patients who suffer from OAB or BOO with persistent nocturia despite treatment may have underlying nocturnal polyuria as well.1 These findings are consistent regardless of gender, age, ethnicity and/or country;1 this discovery suggests NP can have its own pathology.1 A fuller understanding of the underlying causes of nocturia and correct diagnosis of patients suffering from nocturnal polyuria will help clinicians provide better patient care.

Common nocturia causes

Adapted from: Van Karrebroeck et al. Neurourol Urodyn 2002;21:179-183.6 Copyright © 2002.

For more information, download our differentiation guide for further guidance in correctly diagnosis the aetiology of nocturia symptoms in your patients.

Nocturnal polyuria is an important contributing factor to nocturia

Common conditions causing nocturia7,8
Overactive bladder (OAB)9–12 Bladder outlet obstruction (BOO)1,12–16 Nocturnal polyuria (NP)1,6,12,17,18
Description Muscles of bladder start to contract involuntarily even when volume of urine in bladder is low Blockage to the base of the bladder, reducing or stopping the flow of urine into the urethra Passing of large volumes of urine at night due to absence of diurnal rhythm of antidiuretic hormone (ADH) system

24-hour urine output is normal or only moderately increased

Gender Female & male Male > female Female = male
Symptoms Nocturia, urinary incontinence, urinary urgency, increased frequency of urination, sleep disturbance, fatigue Abdominal pain, frequent urination, dysuria, hesitancy, poor stream, intermittent stream, terminal dribbling, nocturia, urinary tract infection, sleep disturbance Nocturia, sleep disturbance
Causes Multifactorial

Specific cause of OAB is still unknown

Large prevalence due to benign prostatic hyperplasia among men

Can be idiopathic

Risk factors for development Elderly patients with cognitive decline Largely dependent on cause Largely dependent on cause
Diagnosis Medical history

Physical exam

Urine sample

Neurological exam

Fluid and bladder diary

Physical exam

Digital rectal exam

Blood chemistries

Prostate-specific antigen testing

Cystoscopy and retrograde urethrogram


Urodynamic testing


Urinalysis / urine culture

Medical history

3-day bladder diary

ADH levels

Treatment Behavioural strategies such as pelvic floor exercises or scheduled toilet trips

Lifestyle modifications such as fluid restriction



Bladder injections (e.g. botox)

Invasive/non-invasive nerve stimulation

Surgery (last resort)

Largely dependent on cause

Urinary catheterisation


  • 5-alpha reductase inhibitors
  • Alpha-1-adrenoreceptor antagonists
  • Trans-urethral resection of prostate (TURP)
  • Laser prostatectomy
Largely dependent on cause

Fluid restriction

Lifestyle modification

ADH analogues (desmopressin)

  • Nocturnal polyuria – often the underlying cause of noctuia1
  • Noqdirna – proven to reduce bothersome nigh time voiding19,20
  • The only licensed medication for the treatment of nocturnal polyuria including the over 65s21

Prescribing Information and Adverse Event Reporting

Noqdirna prescribing information can be downloaded here. Alternatively the SmPC can be accessed via the EMC website.

Adverse events should be reported. Reporting forms and information can be found at www.mhra.gov.uk/yellowcard.

Adverse events should also be reported to Ferring Pharmaceuticals Ltd.

Tel: 0844 931 0050, Email: medical@ferring.com

Are you a Health Care Professional?

The following information is intended for UK Healthcare Professionals (HCPs). It contains information about prescribing, plus relevant patient information.

UY/2407/2017/UK September 2017