The fоllоwing is the mechаnism оf аction of doxаzosin: (1)1. Binds to β3 receptors to stimulate relaxation of the detrusor smooth muscle 2. Stimulates peripheral vasoconstriction and an increase in blood pressure3. Inhibits the degradation of nitric oxide by the enzyme phosphodiesterase 5 4. Inhibits the conversion of testosterone to dihydrotestosterone5. Blocks the α1A- and α1B-receptors in the prostate to cause prostatic smooth muscle relaxation