Tamsulosin: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
Tamsulosin: clinical details
Prescribing considerations
- Exclude other causes of lower urinary tract symptoms before treatment; prostate examination and PSA assessment may be appropriate.
- Assess postural symptoms and concurrent blood-pressure-lowering medicines.
- Ask about planned cataract or glaucoma surgery and communicate current or previous exposure to the ophthalmic team.
- Review CYP3A4 inhibitors and possible CYP2D6 poor-metaboliser status where clinically relevant.
- Use caution in severe renal impairment because this population has not been adequately studied.
Contraindications and cautions
- Hypersensitivity to tamsulosin or product excipients, including previous drug-induced angioedema where specified
- History of orthostatic hypotension
- Severe hepatic insufficiency
Monitoring
- Urinary symptom response and evidence of an alternative diagnosis
- Dizziness, postural hypotension or syncope
- Prostate assessment and PSA where clinically appropriate
- Adverse sexual effects and medicine interactions
- Cataract or glaucoma surgical plans
Clinical pharmacology
Tamsulosin is a selective, competitive postsynaptic alpha-1 antagonist with particular activity at alpha-1A receptors. Relaxation of prostatic and urethral smooth muscle improves urinary flow. It is highly protein-bound and undergoes slow hepatic metabolism involving CYP3A4 and CYP2D6.
Formulation and product differences
- Products include prolonged-release tablets and modified- or prolonged-release hard capsules.
- Food instructions are product-specific: some products may be taken with or without food, while others specify administration after the first meal.
- Modified- or prolonged-release formulations must be swallowed intact.
- Excipients differ: the selected tablet contains lactose, while the SUN Pharma capsule contains colouring agents that may cause allergic reactions.
Tamsulosin preparations and strengths
Capsule
Route: Oral
Strengths: 400 micrograms
Modified-release tablet
Route: Oral
Strengths: 400 micrograms
Tamsulosin interactions
Check for medicines that lower blood pressure or alter tamsulosin metabolism. Evidence about herbal interactions is limited.
Other alpha-blockers
Combining them can increase postural hypotension, dizziness or fainting.
Antihypertensives, nitrates, baclofen, levodopa and anaesthetic agents
Additive blood-pressure lowering may cause dizziness, weakness or syncope.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.