Adult 50 mg 1 hr before sexual activity. Max: 100 mg once daily. Impaired renal & hepatic function 25 mg. Patients using other drugs given the extent of the interactions w/ patients receiving concomitant therapy w/ ritonavir: Not to exceed max 25 mg as single dose in 48-hr period.
Consider CV status of the patient prior to initiating therapy. Patients w/ underlying conditions eg, vasodilatory effects especially in combination w/ sexual activity. Not recommended in patients w/ anatomical deformation of the penis eg, angulation, cavernal fibrosis or Peyronie's disease, or conditions which may predispose to priapism. Co-administration w/ α-blocker. Potentiates the anti-aggregatory effect of Na nitroprusside. Patients w/ bleeding disorders or active peptic ulceration; retinitis pigmentosa. May affect ability to drive or operate machinery.