II. Indications

  1. Hypertension
    1. Not first-line Antihypertensives, and avoid using as monotherapy (higher risk of CVA and CHF)
  2. Benign Prostatic Hypertrophy
    1. Selective Alpha-1a Antagonists (e.g. Tamsulosin) are preferred
  3. Medical Expulsive Therapy for Ureteral Stone
    1. Replaced by the preferred Selective Alpha-1a Antagonists (e.g. Tamsulosin)

III. Dosing

  1. Hypertension
    1. Start: 1 mg orally at bedtime and titrate dose (Maximum 16 mg/day)
  2. Benign Prostatic Hypertrophy (replaced by Selective Alpha-1a Antagonists)
    1. Start: 1 mg orally at bedtime and titrate every 1-2 weeks doubling dose, to a maximum of 8 mg at bedtime
    2. Extended release formulation (e.g. Cardura XL) 4 mg in am daily (may increase to 8 mg daily after 3-4 weeks)
  3. Medical Expulsive Therapy for Ureteral Stone (replaced by Selective Alpha-1a Antagonists)
    1. Extended release formulation (e.g. Cardura XL) 4 mg orally daily (not FDA approved)

IV. Safety

  1. Unknown safety in Pregnancy
  2. Unknown safety in Lactation

V. Mechanism

  1. See Alpha Adrenergic Receptor (Alpha-1 Antagonist)
  2. Peripheral Alpha-1 Adrenergic Antagonist
    1. Arterial and Venous Vasodilation

VII. Drug Interactions

  1. Strong CYP3A4 Inhibitors (e.g. Clarithromycin, Itraconazole)
    1. Risk of increased Doxazosin effects (e.g. Orthostatic Hypotension)

IX. References

  1. (2020) Med Lett Drugs Ther 62(1598): 73-80
  2. Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 62-3
  3. Hamilton (2020) Tarascon Pocket Pharmacopoeia

Images: Related links to external sites (from Bing)

Related Studies

Cost: Medications

doxazosin (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
DOXAZOSIN MESYLATE 1 MG TAB Generic $0.09 each
DOXAZOSIN MESYLATE 2 MG TAB Generic $0.07 each
DOXAZOSIN MESYLATE 4 MG TAB Generic $0.09 each
DOXAZOSIN MESYLATE 8 MG TAB Generic $0.11 each