01Purpose and principlesWhat the treatment does and how it fits into care.
Medical expulsive therapy aims to relax ureteric smooth muscle and improve the chance that a stone traverses the remaining ureter. It does not fragment the stone, sterilise infected urine or relieve a dangerous obstruction reliably. Its place therefore follows a decision that observation is medically acceptable. The discussion concerns whether an additional medicine is worthwhile during observation, rather than whether a medicine can substitute for drainage or a needed procedure.
Guidelines describe overlapping but different populations. NICE NG118 says to consider alpha blockers for distal ureteric stones smaller than 10 mm, including its separately stated child and young-person population. EAU 2026 gives a strong recommendation to offer alpha blockers as one option for distal stones 5–10 mm and describes the greatest benefit above 5 mm. A5 mm stone is within that EAU recommendation, while exactly 10 mm is outside the NICE less-than 10 mm wording. Do not silently replace either inequality or extend distal evidence to every renal or proximal stone.
Trial results explain why benefit should be discussed selectively. In the adult Furyk trial, tamsulosin 0.4 mg daily for 28 days did not significantly improve overall passage for all included distal stones up to 10 mm. Its prespecified 5–10 mm subgroup showed a passage advantage, but that does not prove equal benefit for each patient, and overall pain, intervention and analgesic outcomes did not differ. The regimen supplies a studied duration for a bounded adult treatment plan; it does not establish that a patient must finish four weeks despite a reason to stop.
The selected Zentiva 400 microgram prolonged-release capsule is licensed for male lower urinary tract symptoms associated with benign prostatic hyperplasia. That licence supplies formulation and safety information, not a licensed stone indication. Adult stone guidance is not restricted to men simply because the product licence is for BPH. Explain off-label use, the uncertain individual benefit and the alternatives; pregnancy and under-eighteen use need their own specialist assessment and cannot inherit the adult case prescription.
Key points
- Medical expulsive therapy is an optional aid to passage in a selected stable patient; infection, refractory pain or deteriorating renal function require reassessment and can make active treatment necessary.
- NICE considers alpha blockers for distal ureteric stones below 10 mm. EAU 2026 offers them as an option for distal stones 5–10 mm, with the greatest expected benefit in stones above 5 mm; explain the source-specific boundary.
- Tamsulosin for stone passage is off-label. A studied adult regimen is 400 micrograms orally daily for up to 28 days, with earlier review and cessation for passage, complications or adverse effects;28 days is not a compulsory guideline course.
- The selected prolonged-release capsule is swallowed whole after breakfast or the first meal. Screen for previous orthostatic hypotension, severe hepatic impairment, interacting medicines and planned cataract or glaucoma surgery before starting.
- Dizziness or weakness requires sitting or lying down and blood-pressure assessment. Angioedema requires immediate cessation and urgent treatment; the selected product must not be readministered after this reaction.
- At follow-up, document symptoms, drug tolerance and evidence of passage or continued obstruction. A prescription ending without a stone outcome is an incomplete episode of care.
02Indications, selection and cautionsWho may benefit, who needs urgent treatment and important alternatives.
Confirm a distal ureteric stone, controlled pain, adequate oral intake, no infection and no threatened renal function. Review solitary-kidney or bilateral disease and persistent obstruction with urology. The desire to avoid an operation does not remove a clinical indication for active treatment.
Ask about previous orthostatic hypotension, syncope, falls, current dizziness and blood-pressure-lowering medicines. A history of orthostatic hypotension is a contraindication for this selected product, rather than simply a reason to give the same prescription with a leaflet. Record a relevant baseline blood-pressure assessment.
Check both planned cataract and glaucoma surgery and any previous alpha-blocker use. Intraoperative floppy iris syndrome can complicate these operations; starting tamsulosin when such surgery is scheduled is not recommended. Stopping shortly before surgery has uncertain benefit, so inform the ophthalmic team instead of promising that a short washout removes the risk.
New fever, shaking chills, persistent vomiting, severe recurrent pain or reduced urine output should interrupt the outpatient plan. Renal deterioration or infected obstruction warrants urgent assessment, even if the original scan suggested a favourable size. Drug intolerance may end MET while observation or a procedure remains appropriate.
03Assessment before treatmentTests and checks that guide safe selection.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Review the diagnostic imagingFirst step - Why
- Check that the stone fits the evidence population and identify obstruction.
- Interpretation and limitations
- Read the maximal reported diameter and ureteric segment. A seven-millimetre distal stone and a seven-millimetre renal calyceal stone have different natural histories and are not interchangeable MET indications. Persistent obstruction on reassessment can favour removal despite symptom improvement.
- 02
Renal function, urine and infection assessment - Why
- Exclude a complication that makes simple outpatient passage therapy unsuitable.
- Interpretation and limitations
- Compare creatinine with baseline and obtain urine culture when infection is suspected. Use systemic observations and the clinical course alongside urine tests; negative nitrites do not exclude infection. Do not postpone source-control assessment while waiting for a culture result in a systemically unwell obstructed patient.
- 03
Prescribing and postural assessment - Why
- Identify contraindications and interactions before the first dose.
- Interpretation and limitations
- Reconcile antihypertensives, other alpha blockers and CYP3A4 inhibitors, and ask about hepatic disease and eye surgery. Measure sitting and standing pressure when the history suggests postural symptoms. The aim is a concrete decision to prescribe, modify the plan or avoid treatment, not collection of an unused blood-pressure value.
- 04
Passage and recovery assessment - Why
- Determine whether the treatment episode has reached its intended endpoint.
- Interpretation and limitations
- Ask the patient to retain any passed material. Select imaging when passage is uncertain or obstruction needs reassessment, and confirm recovery of renal function when previously affected. A completed prescription, improved pain score or a new stent does not itself demonstrate stone clearance.
04Treatment approachPreparation, options, escalation and aftercare.
01Worked caseA selected adult completes a monitored trialFirst stepA fifty two year old man has a seven-millimetre distal ureteric stone, controlled pain and creatinine at baseline.+
- 1He is afebrile, can drink and has no solitary kidney, bilateral obstruction or current reason for urgent stone removal. Medicines reconciliation finds no interacting alpha blocker or strong CYP3A4 inhibitor; there is no orthostatic history, severe liver disease or planned eye operation. The clinician explains the NICE and EAU populations, the greater potential benefit for this stone size and the off-label nature of treatment.
- 2He chooses a monitored trial and starts the selected tamsulosin 400 microgram prolonged-release capsule orally once daily after breakfast, swallowed whole. The prescription has a maximum planned duration of 28 days, using the studied adult regimen, with an earlier review and instructions to stop and seek assessment for infection, renal deterioration, refractory pain or important adverse effects. This maximum does not oblige him to continue after passage.
- 3At the individual one-week review he reports no dizziness or falls, has a stable postural blood-pressure assessment and has had only brief manageable discomfort. He continues the agreed plan. On day sixteen he captures a stone; the clinician stops tamsulosin, sends the material for analysis and reviews whether the initial obstruction has resolved.
- 4Follow-up ultrasound shows resolution of the earlier dilation and creatinine remains at his baseline. The record closes the passage episode with stone recovery and concordant renal assessment, then moves to recurrence prevention. His successful outcome is an observed fictional case, not evidence that the medicine guarantees passage or that every patient needs this imaging interval.
02Treatment is poorly toleratedRespond to new postural symptomsA patient taking tamsulosin develops dizziness on standing during an otherwise uncomplicated observation period.+
- 1Ask the patient to sit or lie down, assess blood pressure, hydration and other causes, and review the medicine list. Syncope, injury or persistent hypotension requires urgent clinical assessment. Withhold further tamsulosin while the prescriber assesses the reaction rather than advising the patient to push through it until the course is complete.
- 2Reconsider the balance of benefit and harm with the patient. If MET is stopped, establish whether the stone can still be observed safely or whether pain, obstruction or preference now favours a procedure. Removing the adjunct does not make the stone episode disappear.
- 3Document the adverse effect and communicate the revised plan. Angioedema is a different and potentially life-threatening reaction: stop treatment immediately, treat urgently and do not readminister the implicated tamsulosin product.
03Observation reaches an intervention decisionAct on persistent stone or a clinical stop criterionThe patient remains obstructed, develops a complication or no longer tolerates waiting.+
- 1Use symptoms, renal tests and appropriate imaging to distinguish persistent stone from presumed passage. Infection, refractory pain or deteriorating renal function terminates a conservative MET strategy. Arrange emergency drainage assessment for infected obstruction or anuria; do not wait for the prescription end date.
- 2For an adult with pain that remains intolerable or a stone judged unlikely to pass, offer treatment within the NICE forty-eight-hour diagnosis or readmission window. In a stable patient without that immediate indication, agree the timing and method of active removal from stone location, size, anatomy and preference.
- 3DefinitiveReconcile the unused medicine and any planned procedure. If a temporary drain is inserted, record definitive stone treatment and device follow-up separately. Explain that failure to pass during a monitored interval is a reason to reconsider treatment, not a reason to extend successive prescriptions without checking obstruction.
05Regimens, contraindications and interactionsTreatment details and the circumstances that modify them.
Tamsulosin 400 microgram prolonged-release capsules, selected Zentiva product
For a selected stable adult with a distal ureteric stone, off-label 400 micrograms orally once daily after breakfast or the first meal; swallow whole. A studied regimen lasts up to 28 days, with individual earlier review and stop on confirmed passage, a complication or intolerance. Do not crush or chew, increase the dose to force passage or treat 28 days as a compulsory course.Contraindicated with a history of orthostatic hypotension, severe hepatic insufficiency or hypersensitivity including drug-induced angioedema. Renal impairment needs no routine dose adjustment, but CrCl below 10 mL/min was not studied: use specialist caution. Mild or moderate hepatic impairment needs no adjustment. Check postural symptoms and interacting medicines; other alpha blockers increase hypotension. Do not combine strong CYP3A4 inhibitors with tamsulosin in a CYP2D6 poor metaboliser, and use caution with strong or moderate CYP3A4 inhibitors generally. Initiation before scheduled cataract or glaucoma surgery is not recommended; tell the eye surgeon about current or past use. Sit or lie down for dizziness or weakness and obtain assessment; stop immediately for angioedema and do not readminister. The selected licence is BPH, not stone passage; do not extrapolate this adult regimen to pregnancy or children.
06Complications, monitoring and follow-upAdverse effects, response and longer-term review.
- Arrange a named review with access instructions for worsening symptoms; review timing is individual and should occur before a prescription silently rolls into another month.
- Ask specifically about dizziness, fainting, falls, weakness, ejaculation changes and new medicines; a tolerability assessment should influence continuation.
- Reassess fever, pain burden, oral intake, urine output and renal function when clinically indicated; a good initial scan does not exclude a later complication.
- Record the final stone outcome and stop date, including whether passage was recovered or imaged, renal recovery was checked and a procedure or device review remains outstanding.
07Special situationsVariants, exceptions and circumstances that change the usual approach.
Boundary words matter
The NICE less-than 10 mm population excludes exactly 10 mm, whereas the EAU 2026 five-to-ten-millimetre recommendation includes that boundary. A source-specific explanation is more accurate than manufacturing a single universal threshold.
A licensed formulation can have an off-label use
Using the correct capsule and dose does not convert MET into a licensed indication. The stone guideline and adult trial support the clinical rationale, while the SmPC supports formulation handling and safety; each source has a different job.
A duration is a maximum within a plan
The twenty-eight-day trial regimen provides one defensible adult schedule. Earlier successful passage, adverse effects or complications change that plan, and a stable nonpassing stone still needs reassessment rather than reflex renewal.
Benefit has several possible meanings
A higher passage rate in a selected subgroup does not establish equivalent reductions in pain, analgesic use, intervention or time away from work. Counselling should identify which outcome the evidence supports and which burden matters most to the patient.
08Common pitfallsFrequent interpretation and management errors.
- 01
Prescribing because a CT report contains the word stone without checking that it is distal ureteric disease applies evidence to the wrong anatomical problem.
- 02
Giving a BPH prescription without an off-label discussion, review or stop criteria leaves the purpose and endpoint unclear.
- 03
Treating tamsulosin as analgesia or source control can postpone a necessary response to severe pain or infected obstruction.
- 04
Overlooking previous orthostatic hypotension or scheduled eye surgery can expose a patient to avoidable product-specific harm.