PSA (Prostate Specific Antigen) count is used to diagnose prostate cancer or BPH (Benign Prostate Hypertrophy). If a man has BPH, the drugs taken to shrink the prostate, Proscar and Avodart, will lower the PSA levels as the prostate shrinks. In obese men, losing weight can also lower PSA levels. Taking care of yourself and taking the steps to reduce the risk of prostate cancer can keep your levels low. For more information, visit http://www.ask.com/wiki/Prostate_cancer_screening.