What is the recommended dosage and treatment protocol for Terazosin (alpha-blocker) in patients with benign prostatic hyperplasia (BPH) and hypertension?

Terazosin Dosage and Treatment Protocol for BPH and Hypertension

For patients with both BPH and hypertension, terazosin should be initiated at 1 mg at bedtime, with gradual titration up to 10 mg once daily to achieve optimal symptom relief, with careful monitoring of blood pressure effects. 1

Initial Dosing and Titration

• Starting dose: 1 mg at bedtime for ALL patients (this dose should never be exceeded initially) 1
• Titration schedule: Increase in stepwise fashion to:
  • 2 mg once daily
  • 5 mg once daily
  • 10 mg once daily 1
• Duration for assessment: 4-6 weeks at 10 mg dose is generally required to evaluate clinical response 1
• Maximum effective dose: 10 mg is typically the target dose for most patients with BPH 2

Special Considerations for Patients with Hypertension

• Terazosin can effectively treat both BPH and hypertension simultaneously 3
• Blood pressure monitoring:
  • Check BP at end of dosing interval to ensure 24-hour control
  • Consider measuring BP 2-3 hours post-dose to assess maximum effect 1
• Important caution: In men with hypertension and cardiac risk factors, terazosin monotherapy may be insufficient for optimal hypertension management and separate antihypertensive therapy may be required 2

Expected Outcomes

• BPH symptom improvement: 4-6 point improvement in AUA Symptom Index 2
• Urinary flow: Average increase of 2 ml/s in peak urinary flow rate 4
• Blood pressure effects:
  • Minimal BP reductions in normotensive patients
  • Clinically significant BP reductions in untreated hypertensive patients
  • Generally safe with concomitant antihypertensive medications 5, 3

Potential Adverse Effects

• Common side effects: Orthostatic hypotension, dizziness, tiredness (asthenia), ejaculatory problems, nasal congestion 2
• Most common reasons for discontinuation: Dizziness (2.0%) and headache (1.1%) 5
• Risk of syncope: Rare (0.6% of patients), most likely during initiation or dose escalation 5

Important Clinical Pearls

• If terazosin is discontinued for several days or longer, therapy must be reinitiated using the initial 1 mg dosing regimen 1
• Elderly patients (≥65 years) may experience slightly more postural symptoms and dizziness, but the difference is not statistically significant 5
• Terazosin has been shown to be safe and effective even in men over 80 years of age 6
• When used with other antihypertensive agents (especially calcium channel blocker verapamil), dose reduction and retitration may be necessary to avoid significant hypotension 1
• Terazosin has shown favorable effects on lipid profiles, with increases in HDL:cholesterol ratio and reductions in total cholesterol, LDL, and triglycerides 5

Comparative Efficacy Among Alpha Blockers

• Alfuzosin, doxazosin, tamsulosin, and terazosin are all considered appropriate treatment options for LUTS secondary to BPH with equal clinical effectiveness 2
• Tamsulosin appears to have a lower probability of orthostatic hypotension but higher probability of ejaculatory dysfunction compared to terazosin 2
• Terazosin may provide significantly better symptom improvement compared to tamsulosin in some studies 7

By following this dosing protocol and monitoring guidelines, terazosin can effectively manage both BPH and hypertension while minimizing adverse effects.