Erectile Recovery After Robotic-Assisted Laparoscopic Prostatectomy

Inclusion Criteria:

1. Patients who have had a prostate biopsy positive for prostate cancer.
2. Patient must be age 30 - 89 years.
3. Patient must be willing to sign the Institutional Review Board approved consent.
4. Patient must have had (or be about to undergo) bilateral or unilateral nerve sparing RALP.
5. Patient must have an International IIEF equal to or greater than 21.

Exclusion Criteria:

1. Patients with known unstable angina, uncontrolled hypertension, congestive heart failure, or cardiovascular accident within the preceding 2 weeks.
2. Patients being treated with nitrate therapy.
3. Patients with significant renal or hepatic impairment, cerebrovascular disease.
4. Patients with prior erectile dysfunction as indicated by the initial IIEF.
5. Patients younger than 30 years of age.
6. Patients who did/will not have a unilateral or bilateral nerve sparing radical prostatectomy.
7. Patients who have had a prior reaction to Sildenafil or pentoxifylline.
8. Patients taking any potent inhibitor of cytochrome P450 3A4 (e.g., ketoconazole, itraconazole, erythromycin, etc.).
9. Patients with a clinically significant abnormality on preoperative ECG that in the opinion of the investigator may increase the patient's cardiovascular risk in this study.
10. Patients with a history of left ventricular outflow obstruction (e.g. aortic stenosis, idiopathic hypertrophic subaortic stenosis).
11. Patients with resting hypotension (BP \< 90/50 mm Hg), or resting hypertension (BP \> 170/110 mm Hg).
12. Patients with retinitis pigmentosa.
13. Patients with a bleeding disorder.
14. Patients with active peptic ulceration.
15. Patients with conditions that may predispose to priapism (e.g. sickle cell anemia, multiple myeloma, or leukemia).
16. Patients who have previously experienced non-arteritic ischemic optic neuropathy (NAION).