Digoxin for Recurrent Prostate Cancer

This is a pilot phase II, open labeled single center study to assess the efficacy of digoxin on inhibiting PCa progression as measured by PSADT. The participants will take study drug digoxin, which is approved by FDA for the treatment of CHF, 125 or 250 mcg orally daily, titrated to the level of 0.8 - 2 ng/ml for total of 6 cycles (4 weeks/cycle). The lower dose of digoxin (such as 125 mcg/day) will be chosen if serum level reaches 0.8 ng/ml already. Patients may continue another 6 cycles if evident of clinical benefit.