A 69-year-old man with benign prostatic enlargement has taken tamsulosin MR 400 micrograms daily for 5 months. His hesitancy, weak stream and

Question

A 69-year-old man with benign prostatic enlargement has taken tamsulosin MR 400 micrograms daily for 5 months. His hesitancy, weak stream and incomplete emptying have improved substantially. He remains troubled by waking three to four times nightly to pass large volumes of urine. Urine culture is negative, eGFR is 68 mL/min/1.73 m², and post-void residual volume is 55 mL. A 3-day frequency-volume chart confirms nocturnal polyuria. Diabetes mellitus, heart failure, dependent oedema, obstructive sleep apnoea and diuretic use have been excluded. He has already reduced evening fluid intake and caffeine without benefit. His blood pressure is 132/78 mmHg and serum sodium is 140 mmol/L. He takes no medicines associated with hyponatraemia. What is the most appropriate next management plan?

Accepted Answer

Start desmopressin oral lyophilisate 50 micrograms at bedtime, advise overnight fluid restriction, and check serum sodium in the first week and at 1 month

Answer

Start furosemide in the late afternoon and review symptoms after 2 weeks

Answer

Refer routinely for cystoscopy and upper-tract imaging before further treatment

Answer

Add solifenacin 5 mg daily and review symptoms after 4 weeks

Answer

Increase tamsulosin MR to 800 micrograms daily and review symptoms after 4 weeks

Benign prostatic enlargement with persistent nocturia due to idiopathic nocturnal polyuria — MSRA MCQ