Silodosin
RAPAFLO
Pronunciation: sye-lo-DOE-sin
What it isHighly alpha-1A-selective antagonist; benign prostatic hyperplasia.
Why this oneIts exceptional uroselectivity relieves outlet symptoms with less blood-pressure effect than nonselective alpha blockers.
What limits itEjaculatory dysfunction commonly ends treatment; renal impairment requires adjustment, and cataract surgery risks floppy iris.
Silodosin prescription history
Animated chart of estimated U.S. prescriptions per year, BPH meds (1987–2026). Silodosin enters in 2009 (estimated).
FDA-approved for
- BPH (2008)
Principal riskRetrograde ejaculation; intraoperative floppy iris
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.
FDA label
Read the full label on DailyMed ↗
NO BOXED WARNINGS
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Benign prostatic hyperplasia | Adult males | 8 mg QD with a meal | 8 mg QD | 8 mg QD |
Renal Mild (CCr 50-80): no adjustment; moderate (CCr 30-50): 4 mg QD; severe (<30): contraindicated
Hepatic Mild-moderate: no adjustment; severe (Child-Pugh ≥10): contraindicated
Moderate renal impairment (CCr 30-50 mL/min): reduce to 4 mg QD
Instructions
- Take once daily with a meal
- May open capsule and sprinkle powder on a tablespoon of applesauce; swallow within 5 min and follow with cool water
- Do not subdivide capsule contents
Available strengths
- cap 4, 8 mg
Contraindications
- Severe renal impairment (CCr <30 mL/min)
- Severe hepatic impairment (Child-Pugh score ≥10)
- Concomitant strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, ritonavir)
Cautions
- Orthostatic hypotension / syncope
- Do not use with other alpha-blockers
- Rule out prostate carcinoma before therapy
- Intraoperative floppy iris syndrome (cataract surgery)
Adverse reactions
- Retrograde ejaculation
- Dizziness
- Diarrhea
- Orthostatic hypotension
- Headache
- Nasopharyngitis
- Nasal congestion
Pregnancy Not indicated for use in females
Lactation Not indicated for use in females
Cost
Generic entry2017
Open Silodosin in the interactive console ↗
Self-check
- How does silodosin’s BP effect compare with nonselective alpha blockers?
Less blood-pressure effect. - What sexual adverse effect commonly ends silodosin treatment?
Ejaculatory dysfunction.