OBJECTIVE: The utilization of LHRH agonists and anti-androgens in prostate cancer has resulted from both their availability and the substantial regret of patients following orchiectomy.  Previously unavailable, this study describes hormonal therapy resource use by age group and duration from a large payer claims database. METHODS: Male patients were identified in the Synergy data warehouse from 03/1999 to 07/2000 with age > 40, a claim for prostate cancer specific LHRH agonist medication, any additional prescription claim, and continuous medical and pharmacy enrollment.  New cases of LHRH agonist monotherapy (MONO) or combination therapy with anti-androgen (CAB) were defined as no MONO or CAB during the 4 months prior to 3/1999.  Therapy groups were stratified by age group (<65 (younger) and > 65 (older)) and followed until 07/2000.  Descriptive statistics were used to summarize the data.  RESULTS:  582 younger patients and 878 older patients were identified. 93.0% of the younger patients had private insurance compared to 28.2% government and 71.8% private insurance in the older patients.  Average duration of all LHRH agonist use was 26.3 weeks and 33.2 weeks in younger and older patients, respectively (P<0.05).  LHRH agonists were used for < 24 weeks and >48 weeks in 56.4% and 17.6% of younger and in 43.3% and 28.3% of older patients.  Average duration of anti-androgen use for CAB patients was 34.7 and 39.8 weeks in younger (n=80) and older patients (n=117)(P=ns).  Anti-androgens were used for < 24 weeks and >48 weeks in 43.8% and 31.3% of younger and in 40.2% and 36.8% of older patients.  CONCLUSIONS:  The duration of LHRH agonist use by prostate cancer patients varies by age.  Large proportions of patients in both age groups use CAB <24 weeks, suggesting use to protect against testosterone surge.  Additional research is required to verify these results.