Doxazosin dosage, side effects
Doxazosin dosage, side effects:
Generic Name: Doxazosin
Drug Class: Alpha-1 adrenergic receptor antagonist (alpha-blocker)
Brand Names
Doxazosin is sold under various brand names worldwide, including:
United States & Canada
- Cardura (original brand by Pfizer)
- Cardura XL (extended-release formulation)
Europe & Other Regions
- Doxadura (UK)
- Loxzosin (some European countries)
- Alfadil (in some markets)
- Doxacard (alternative brand in some countries)
Forms & Dosages
- Immediate-release tablets: 1 mg, 2 mg, 4 mg, 8 mg
- Extended-release (XL) tablets: 4 mg, 8 mg
Primary Uses
- Hypertension (High Blood Pressure) – Often used in combination with other antihypertensives.
- Benign Prostatic Hyperplasia (BPH) – Helps relax prostate and bladder muscles to improve urine flow.
Mechanism of Action
- Blocks alpha-1 adrenergic receptors in blood vessels and the prostate, leading to:
- Vasodilation (lowers blood pressure)
- Relaxation of bladder neck and prostate (improves BPH symptoms)
Side Effects
- Common: Dizziness, headache, fatigue, edema (swelling), orthostatic hypotension (sudden drop in BP upon standing).
- Less common: Palpitations, nausea, dry mouth, priapism (rare but serious).
Key Considerations
- First-dose effect: Can cause severe hypotension after the first dose; usually started at bedtime.
- Not for acute BPH relief: Takes weeks for full effect on urinary symptoms.
- Avoid with PDE5 inhibitors (e.g., Viagra, Cialis) – Risk of severe low blood pressure.
Similar Drugs in the Same Class
- Terazosin (Hytrin)
- Prazosin (Minipress)
- Tamsulosin (Flomax, more prostate-selective)
