To determine whether the addition of a dual Five Alpha Reductase Inhitor (Dutasteride) will alleviate urinary retention secondary to BPH in who have failed a voiding trial without a catheter. Following treatment with an Alpha Blocker alone.

Inclusion Criteria:

1. Males betewen the ages of 50 and 90 years of age.Written informed consent.
2. Men with acute urinary retention attributed to bladder outlet obstruction caused by BPH, who have failed atleast 1 week trial of alpha blocker treatment.
3. PSA level equal to or greater than 1.5ng/ml and equal to or less than 15 ng/ml.

Exclusion Criteria:

1. Urinary retention attributed to a neurogenic or myogenic bladder dysfunction.
2. Use of psychotrophic medications.
3. Use of antichollinergic medications.
4. Prostate cancer.
5. Allery to five alpha reductase inhibitors.
6. Prior prostate surgery.
7. Urethral stricture.
8. Bladder calculi.
9. Invasive bladder cancer.
10. Inability to understand or agree with the requirements of the study.
11. Any investigational drug received within 30 days prior of study entry.