Terazosin

Introduction

Last week, I encountered a prescription written: "Terazosin 1 mg OD for 3 days, then followed by 2 mg OD for 10 days", with the next clinic appointment 2-3 months later.

Indications

Although terazosin is commonly used for benign prostatic hyperplasia (BPH) management (a long-term management), it can also be used off-label for ureteral stone(s) expulsion.

Lexicomp:

• Consider for use in patients with ureteral stones >5 and ≤10 mm. Additionally, may consider for use after shock wave lithotripsy to help pass stone fragments.
• Adult, oral, 2 to 5 mg at bedtime until stone passage or for up to 4 weeks.

NOTE:

• Terazosin relaxes the smooth muscle of the bladder, thus reducing bladder outlet obstruction.
• Among alpha-blockers, silodosin, tamsulosin and alfuzosin have less effect on BP than prazosin or terazosin and may be a better choice for BPH.

Dosage Titration

Since alpha-blockers may lead to postural hypotension, hence it is a common practice to start it at lower dose, and then titrate up.

I will normally counsel the patient to take the dose at night, and warn him that he may experience post-dose dizziness.

• He should get up gradually from sitting or lying to minimize the side effect.
• Over time, his body may get used to the side effect.

External Links

• Efficacy of three different alpha 1-adrenergic blockers and hyoscine N-butylbromide for distal ureteral stones, 2011
  
• Adjunctive medical therapy with α-blocker after extracorporeal shock wave lithotripsy of renal and ureteral stones: a meta-analysis, 2015