The effects and duration of action of bedtime administration of doxazosin 2 mg for 4 weeks on uncontrolled morning home hypertension were investigated. Morning home blood pressure (HBP) was significantly lowered by bedtime administration of doxazosin. Doxazosin significantly lowered evening HBP only in the subgroup of patients with an uncontrolled evening HBP. The evening (E)/morning (M) ratio was greater in patients with an uncontrolled evening HBP than in those with a controlled evening HBP. The results suggest that bedtime administration of doxazosin effectively suppresses morning HBP in uncontrolled morning hypertensives and lowers evening HBP in uncontrolled evening hypertensives.