What is Rezum therapy?

Rezum (manufactured by Boston Scientific) is a minimally invasive treatment for benign prostatic hyperplasia — the common, non-cancerous enlargement of the prostate that affects over half of men in their sixties. The procedure uses convective water vapour thermal therapy (WVTT): a small cystoscope is passed through the urethra and a retractable needle delivers brief bursts of steam (water vapour at 103°C) directly into the obstructing prostate tissue.

The thermal energy from the steam destroys the targeted cells. Over 3–6 months, the immune system absorbs this treated tissue, the prostate shrinks in volume (typically by approximately 30–34%), and urinary symptoms progressively improve. Because the procedure targets only the obstructing tissue — not the ejaculatory ducts — sexual function is preserved far better than with TURP.

Clinical evidence: A 2025 expert consensus published in BJUI Compass confirms Rezum as a minimally invasive option with low retreatment rates and preserved sexual function. Real-world data from over 250 cases confirms IPSS symptom scores improve by approximately 50% and urine flow (Qmax) improves by 7 ml/s on average. BAUS BPH resources →

Who is suited to Rezum?

Rezum is an excellent option for men who:

  • Have moderate to severe BPH symptoms (IPSS ≥ 8) not controlled by medication
  • Want to avoid general anaesthetic and overnight hospital admission
  • Wish to preserve ejaculatory and erectile function
  • Have a prostate volume of 30–80 ml (ideal range)
  • Have a prostate with or without a small median lobe (Rezum can treat median lobes, unlike Urolift)
  • Have confirmed BPH — cancer must be excluded before any BPH procedure

Rezum is generally less suited to men with very large prostates (above 80 ml), large median lobes, or those in urinary retention — where Aquablation or TURP produce more reliable results.

How Rezum is performed

01
Preparation and anaesthetic
Rezum is most commonly performed under local anaesthetic with intravenous sedation — no general anaesthetic is required for most patients. You will typically attend as a day case. A short course of prophylactic antibiotics is given before the procedure.
02
Cystoscope placement
A slim cystoscope is passed through the urethra to visualise the prostate. This allows the surgeon to assess the anatomy and plan how many steam injections are needed based on the size and shape of the obstructing tissue.
03
Targeted steam injections
A small retractable needle is deployed into the prostate tissue. Each 9-second injection delivers water vapour at 103°C, which diffuses through the tissue and causes cell death in the targeted zone. Multiple injections are placed at different sites — typically 3–12 depending on prostate size. Each session takes 15–30 minutes in total.
04
Catheter placement
Because temporary prostate swelling can briefly worsen urine flow, a catheter is left in place for 3–7 days while initial inflammation settles. Most patients manage this at home and are instructed on catheter care before discharge.
05
Tissue absorption — the 3–6 month process
After catheter removal, the body's immune system gradually clears the treated tissue. Urinary symptoms improve progressively over 3–6 months as the prostate shrinks. Studies show a consistent volume reduction of approximately 30–34% by 3 months.

Recovery after Rezum

TimeframeWhat to expect
Day 0Day case — home the same day. Catheter in situ. Some burning or discomfort on the day is normal. Rest advised.
Day 3–7Catheter removed in clinic or by district nurse. Urgency and frequency common initially. Drink plenty of fluids.
Week 1–2Return to desk work and light activity for most men. Avoid strenuous exercise, alcohol and spicy food. Urinary symptoms may fluctuate.
Month 1–3Progressive improvement in flow rate and symptoms as treated tissue is absorbed. Bladder urgency usually settles. Most men notice meaningful improvement by week 6–12.
Month 3–6Full benefit established. IPSS symptom scores typically 50% lower than before treatment. Three-month outpatient review with urine flow assessment.
Year 1–5Durable results confirmed in pivotal trial at 5 years. Retreatment rate approximately 4–11%. Annual review recommended.

Risks and side effects

Rezum has an excellent safety profile — one of its main advantages over TURP and Aquablation.

Very common (temporary)

Urgency and frequency

Irritative urinary symptoms are common in the first 4–6 weeks as the prostate heals. These typically resolve completely as the tissue is absorbed. Alpha-blocker medication can help during this period.

Common

Short-term urinary retention

Due to post-operative swelling. Managed with the short-term catheter (3–7 days). Rarely, a longer catheterisation period or repeat procedure is needed.

Uncommon

Urinary tract infection

Prophylactic antibiotics are routinely given. UTI in the post-operative period is treated with a course of oral antibiotics.

Rare (<2%)

Retrograde ejaculation

Significantly rarer with Rezum than with TURP or Aquablation. Published data confirms ejaculatory function is preserved in the large majority of men — a key advantage for sexually active patients.

Very rare

Haematuria (blood in urine)

Some blood-staining of urine is normal and expected for a short period after catheter removal. Significant bleeding requiring intervention is very uncommon with Rezum.

Rare

Retreatment needed

Approximately 4–11% of men require further treatment within 5 years. All BPH treatments carry some retreatment risk, particularly as the prostate continues to grow with age.

Frequently asked questions

Rezum does not produce immediate symptom relief. As treated tissue is absorbed over 3–6 months, symptoms progressively improve. Most men notice meaningful improvement at 3 months, with full benefit by 6 months. IPSS symptom scores typically improve by approximately 50% from baseline; urine flow (Qmax) improves by an average of 7 ml/s.

This depends on your specific anticoagulant and why you are taking it. For many patients on warfarin, rivaroxaban, apixaban or similar, a short pause (typically 5–7 days) before Rezum is all that is needed — and because Rezum has a very low bleeding risk, the interruption period is shorter than for TURP or Aquablation. This will be reviewed carefully at your pre-operative assessment.

Both are day-case, sexual-function-preserving treatments for BPH, but they work differently. Urolift uses small permanent implants to hold the prostate lobes apart — producing immediate symptom improvement. Rezum destroys tissue with steam, which is then absorbed — so improvement is gradual over 3–6 months but the prostate genuinely reduces in size. Rezum can treat a median lobe; Urolift cannot. Your anatomy and personal preferences guide the choice.

Yes. If symptoms return — which occurs in approximately 4–11% of men within 5 years — Rezum can be repeated, or alternative treatments including Aquablation or TURP can be considered. Because Rezum does not alter the urethral anatomy, all subsequent treatment options remain available.

Yes. Because Rezum is performed under local anaesthetic or light sedation, it is well tolerated by older men and those with medical comorbidities including diabetes, heart conditions or chronic lung disease — groups who may not be fit for general anaesthetic. Published Italian data confirms Rezum is safe and feasible in frail and elderly men.

Is Rezum right for you?

An initial consultation with Mr Ameen includes assessment of your prostate volume, urine flow studies, symptom scoring, and a personalised recommendation comparing Rezum, Aquablation, TURP and other options. Consultations at Wellington Hospital, Harley Street, Spire Bushey and Chase Lodge — available within days.