Tamsulosin
FLOMAX
Pronunciation: tam-SOO-loe-sin
“Tiramisu losin' Flow maximizer”
What it isAlpha-1A selective antagonist; benign prostatic hyperplasia.
Why this oneUroselective, so it relieves obstruction with less hypotension than the older alpha blockers.
What limits itIntraoperative floppy iris syndrome — the ophthalmologist must be told before cataract surgery. Retrograde ejaculation is common.
FDA-approved for
- BPH (1997)
Off-label
- ureteral stone passage
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Benign prostatic hyperplasia (BPH) signs/symptoms | Adults | 0.4 mg QD | 0.4 mg QD | 0.8 mg QD |
Titration May increase to 0.8 mg QD after 2-4 weeks if inadequate response to 0.4 mg
Renal Not studied in end-stage renal disease
Hepatic Not studied in severe hepatic impairment
Instructions
- Take approximately one-half hour after the same meal each day
- Do not crush, chew, or open capsules
- If discontinued/interrupted for several days, restart at 0.4 mg QD
- Do not use with strong CYP3A4 inhibitors
Available strengths
- cap 0.4 mg
Cautions
- Postural hypotension / syncope — avoid injury-risk situations
- Avoid strong CYP3A4 inhibitors; caution with moderate CYP3A4 or CYP2D6 inhibitors / poor metabolizers
- Do not combine with other alpha-blockers
- Priapism
- Intraoperative Floppy Iris Syndrome — inform ophthalmologist before cataract/glaucoma surgery
Adverse reactions
- Headache
- Dizziness
- Rhinitis
- Abnormal ejaculation
- Asthenia
- Back pain
- Diarrhea
- Somnolence
- Decreased libido
- Blurred vision
Pregnancy Not indicated for use in women
Lactation Not indicated for use in women
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 0.4 mg | cap | 30 qd | $1.50 | offered |
Generic entry2010
NO BOXED WARNINGS
Principal riskOrthostatic hypotension and 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.
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