NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Updated July 13, 2026

Silodosin

Prescription ·Exploratory record · not publication-reviewed ·Updated July 13, 2026

Silodosin is an oral alpha-1A adrenergic blocker used to improve lower urinary tract symptoms from benign prostatic hyperplasia. It relaxes smooth muscle in the prostate, bladder neck, and urethra, but can cause orthostatic hypotension, dizziness, and a high rate of ejaculatory dysfunction; strong CYP3A4 inhibitors and severe renal or hepatic impairment are important safety limits.

Publication status

Exploratory record, not a reviewed medical publication.

See the editorial and medical-review policies for the publication gate.

This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.

In short

What the research says.

A quick, data-only summary. The full evidence, dosing, and sources are below.

Silodosin is an oral alpha-1A adrenergic blocker used to improve lower urinary tract symptoms from benign prostatic hyperplasia. NutriStack rates the supporting evidence as strong. Common adult dosing is Adults: 8 mg orally once daily with a meal. Use 4 mg once daily with a meal in moderate renal impairment; avoid in severe renal impairment., though a prescriber sets the actual dose. This profile indexes 3 sources.

What it's good for
  • Improved urinary flow in benign prostatic hyperplasia1,2
  • Reduced incomplete emptying sensation
  • Reduced weak stream and hesitancy
  • Reduced urinary frequency related to outlet obstruction1,2
What to watch for
  • Retrograde ejaculation or reduced semen volume
  • Dizziness
  • Orthostatic hypotension
  • Severe renal impairment3
  • Severe hepatic impairment3

The bottom line

Evidence rating strong. Most-documented uses: improved urinary flow in benign prostatic hyperplasia, reduced incomplete emptying sensation, reduced weak stream and hesitancy. 3 sources indexed (2009–2026), with 0 interaction records on file.

The science

How it works, mechanistically.

Core mechanism

Silodosin selectively antagonizes alpha-1A receptors that mediate contraction of smooth muscle in the prostate, bladder base, bladder neck, prostatic capsule, and urethra. Blocking these receptors reduces dynamic outlet obstruction and improves urine flow. The drug is metabolized by UGT2B7, alcohol and aldehyde dehydrogenases, CYP3A4, and P-glycoprotein pathways, making renal impairment and CYP3A4/P-glycoprotein interactions clinically relevant.1,2

Class
Uroselective alpha-1A adrenergic blocker
Absorption
Water-soluble; take with food
Dosing

Dosing & protocol.

Common range
Adults: 8 mg orally once daily with a meal. Use 4 mg once daily with a meal in moderate renal impairment; avoid in severe renal impairment.
Recommended form
Oral capsule taken with the same meal each day

Take with a meal to reduce peak-related adverse effects and maintain consistent absorption. Capsules may be opened and sprinkled on applesauce when needed according to labeling.3

Safety

Full safety detail.

Side effects

  • Retrograde ejaculation or reduced semen volume
  • Dizziness
  • Orthostatic hypotension
  • Headache
  • Diarrhea
  • Nasal congestion
  • Syncope rarely
  • Intraoperative floppy iris syndrome risk during cataract surgery

Contraindications

  • Severe renal impairment3
  • Severe hepatic impairment3
  • Concomitant use with strong CYP3A4 inhibitors such as ketoconazole, itraconazole, clarithromycin, or ritonavir3
  • Known hypersensitivity to silodosin1,3
  • Use caution with other blood pressure-lowering drugs or history of orthostatic symptoms2
Sources

Sources, by evidence tier.

Numbered references. Citations throughout the page link here.

Randomized controlled trials

1
  • 1Silodosin therapy for lower urinary tract symptoms in men with benign prostatic hyperplasiaMarks LS et al. · Journal of Urology · 2009

    Clinical trials showed symptom score and urinary flow improvements, with ejaculatory dysfunction and dizziness as common adverse effects.

Reviews & position papers

1
  • 2Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic HyperplasiaAmerican Urological Association · AUA Guideline · 2023

    Guideline supports alpha blockers for bothersome LUTS/BPH and highlights individualized adverse-effect selection.

Reference material

1
  • 3Silodosin Capsules US Prescribing InformationURLU.S. National Library of Medicine · DailyMed · 2026

    Labeling describes 8 mg daily with meal dosing, renal dose reduction, strong CYP3A4 contraindication, orthostatic effects, and ejaculation adverse effects.

FAQ

Common questions.

Quick answers about Silodosin, drawn from the data on this page.

What is Silodosin?

Silodosin is an oral alpha-1A adrenergic blocker used to improve lower urinary tract symptoms from benign prostatic hyperplasia. It relaxes smooth muscle in the prostate, bladder neck, and urethra, but can cause orthostatic hypotension, dizziness, and a high rate of ejaculatory dysfunction; strong CYP3A4 inhibitors and severe renal or hepatic impairment are important safety limits.

What is Silodosin used for?

Commonly cited benefits of Silodosin include: Improved urinary flow in benign prostatic hyperplasia; Reduced incomplete emptying sensation; Reduced weak stream and hesitancy; Reduced urinary frequency related to outlet obstruction. NutriStack rates the overall evidence as strong.

What is a typical dose of Silodosin?

A typical adult dose of Silodosin is Adults: 8 mg orally once daily with a meal. Use 4 mg once daily with a meal in moderate renal impairment; avoid in severe renal impairment.. The commonly recommended form is Oral capsule taken with the same meal each day. These are general ranges, not personalized advice; confirm the right dose with a clinician.

What are the side effects of Silodosin?

Reported side effects include retrograde ejaculation or reduced semen volume, dizziness, orthostatic hypotension, headache, diarrhea, nasal congestion. This is educational information; check with a healthcare professional before use.

How strong is the evidence for Silodosin?

NutriStack rates this as Strong, meaning multiple high-quality meta-analyses or systematic reviews converge on the same finding. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.

Use this with your stack

Silodosin in NutriStack.

Add it to your stack, see how it interacts with everything else you take, and get a Stack Score that updates the moment it does.

NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.