Nocturnal polyuria

This code describes the clinical condition of excessive urine production specifically during nighttime hours, leading to frequent awakenings to void. It signifies a physiological increase in nocturnal urine volume that exceeds bladder capacity or renal concentrating ability.

Use this code when documentation clearly indicates a patient experiences abnormally high urine output at night, distinct from general polyuria or incontinence. Supporting documentation should specify "nocturnal polyuria" or describe symptoms consistent with this condition, such as frequent nighttime urination due to increased urine volume.

• Differentiate from nocturnal enuresis (N39.44), which is involuntary urination during sleep, often without excessive urine production.
• Ensure documentation specifies polyuria (excessive urine volume) at night, not just nocturia (frequent nighttime urination) which may have other causes.
• Consider co-morbid conditions such as heart failure, diabetes, or sleep apnea, which can contribute to nocturnal polyuria, and code them accordingly.