Usual Adult Dose for Hypertension:
Initial dose: 1 mg orally once a day.
Maintenance dose: 1 to 16 mg orally once a day.
Usual Adult Dose for Benign Prostatic Hyperplasia:
Initial dose:
Immediate-release: 1 mg orally once a day.
Extended-release: 4 mg orally once a day with breakfast
Maintenance dose:
Immediate-release: 1 to 8 mg orally once a day.
Extended-release: 4 to 8 mg orally once a day with breakfast. Depending on the patient's symptomatic response and tolerability, the dose may be increased to 8 mg (the maximum recommended dose). The recommended titration interval is 3 to 4 weeks.
If switching from immediate-release doxazosin tablets to extended-release tablets, therapy should be initiated with the lowest dose (4 mg once daily). Prior to starting therapy with doxazosin extended-release tablets, the final evening dose of immediate-release tablets should not be taken. If doxazosin extended-release tablets are discontinued for several days, therapy should be restarted using the 4 mg once daily dose.
Usual Geriatric Dose for Hypertension:
Initial dose: 0.5 mg orally once a day.
 Detailed Doxazosin dosage information
