Does finasteride or moxonidine cause postural hypotension?

Postural Hypotension Risk with Finasteride and Moxonidine

Finasteride does not cause postural hypotension, while alpha-blockers (not moxonidine) are associated with postural hypotension in the treatment of benign prostatic hyperplasia.

Finasteride and Postural Hypotension

• Finasteride, a 5-alpha-reductase inhibitor (5-ARI), is not associated with postural hypotension according to clinical guidelines and drug labeling data 1, 2
• In trials comparing 5-ARIs to alpha-blockers for management of lower urinary tract symptoms, dizziness and postural hypotension were statistically more frequent among patients receiving alpha-blocker therapy, not 5-ARIs 1
• The FDA drug label for finasteride does not list postural hypotension as an adverse effect 2
• Common adverse effects of finasteride include:
  • Sexual dysfunction (erectile dysfunction, decreased libido, ejaculation disorders) 2, 3
  • Gynecomastia 2
  • Breast tenderness 2

Alpha-Blockers and Postural Hypotension

• Alpha-blockers (such as doxazosin, terazosin) are significantly associated with postural hypotension compared to finasteride 3
• In the Medical Therapy of Prostatic Symptoms (MTOPS) study, postural hypotension occurred in:
  • 9.1% of patients on finasteride
  • 16.7% of patients on doxazosin
  • 17.8% of patients on combination therapy (finasteride plus doxazosin)
  • 8.0% of patients on placebo 2
• Finasteride has a significantly lower risk of asthenia, dizziness, and postural hypotension compared to alpha-blockers like doxazosin and terazosin 3

Moxonidine and Postural Hypotension

• There is no specific evidence in the provided materials about moxonidine causing postural hypotension
• Moxonidine is not mentioned in the provided evidence as a medication associated with postural hypotension

Management of Postural Hypotension (When Present)

• First-line pharmacological treatment for postural hypotension is midodrine, with dosage of 10 mg up to three times daily 4
• Second-line options include fludrocortisone (0.1-0.3 mg once daily) 4
• Non-pharmacological management includes:
  • Adequate fluid and salt intake (2-3 L of fluids and 10g of salt daily) 4
  • Physical countermeasures such as leg crossing, squatting, and muscle tensing during position changes 4
  • Compression garments to reduce venous pooling 4

Clinical Implications

• When treating benign prostatic hyperplasia, finasteride is a safer option than alpha-blockers for patients at risk of postural hypotension 3
• For patients requiring both medications, be aware that combination therapy with finasteride and an alpha-blocker has similar rates of postural hypotension as alpha-blocker monotherapy 2
• Monitor patients on alpha-blockers for symptoms of postural hypotension (dizziness, lightheadedness, syncope) 1
• Consider starting with lower doses and titrating gradually in elderly patients who are more susceptible to postural hypotension 4