Agent

Dose

 Adverse Effects

First Generation

α-blocking agents

Doxazosin 

1 mg daily PO initial, increase by 1 mg weekly to desired effect or max dose of 8 mg

Orthostatic hypotension, syncope, dizziness, IOFIS, retrograde ejaculation

Terazosin

1 mg daily, titrate to 2-10 mg to desired effect or maximum dose of 10 mg

See doxazosin

Second Generation α-alpha blocking agents

Tamsulosin 

0.4 mg PO daily initially 30 minutes after the same  meal each day, increased to 0.8 mg in 2-4 weeks if inadequate response.

Retrograde ejaculation, asthenia, dizziness, IOFIS

Alfuzosin ER

10 mg PO daily with the same meal each day

Dizziness, lightheadedness, orthostatic hypotension, IOFIS

Silodosin

8 mg PO daily with the same meal each day, 4 mg PO daily with CrCl 30-50  ml/min, CI with CrCl < 30 ml/min

Retrograde ejaculation, orthostatic hypotension, IOFIS

5-α-Reductase Inhibitors

Finasteride

5 mg PO once daily

Decreased libido, ejaculatory disorder, erectile dysfunction, breast tenderness and gynecomastia

Dutasteride

0.5 mg PO once daily

Decreased libido, ejaculatory disorder, erectile dysfunction

Phosphodiesterase Inhibitor

Tadalafil

5 mg PO once daily decrease to 2.5 mg PO daily with CrCl 30-60 ml/min. Not recommended with hemodialysis

Non-arteritic anterior ischemic optic neuropathy

Antimuscarinics¹

Oxybutynin ER

5-10 mg PO once daily

Constipation, xerostomia, blurred vision, dry eyes, confusion

Tolterodine

1-2 mg PO twice daily, 2-4 mg PO once daily extended relief. Not recommended with CrCl < 10 ml/min or Child-PughClass C

Constipation, xerostomia, angioedema

Solifenacin

5 mg PO once daily, may be increased to 10 mg daily if CrCl > 30 ml/min

See tolterodine, prolonged Qt

Trospium

20 mg PO twice daily at least 1 hour before meals, 60 mg PO daily extended relief at least 1 hour before a meal

Constipation, xerostomia, headache, hypertensive crisis, rhabdomyolysis

Darifenacin

7.5 mg PO once daily, may be increased to 15 mg after two weeks, Child-Pugh Class B or with a CYP3A4 inhibitor do not exceed 7.5 mg, not recommended with Class C

Constipation, xerostomia, headache, angioedema

Β-3 Agonist¹

Mirabegron

25 mg PO daily, may be increased to 50 mg after 4-8 weeks, not recommended with a eGFR < 15 ml/min/1.73 m²

Hypertension, constipation, xerostomia, headache

Vibegron

75 mg PO daily, not recommended with a eGFR < 15 ml/min/1.73 m²

Diarrhea, nausea, headache