OBJECTIVES: To describe the best supportive care costs of psoriasis patients following discontinuation of conventional systemic or biologic therapy. METHODS: Adult patients with ≥ 2 psoriasis diagnoses (from office visits) with continuous insurance coverage ≥ 6 months before (baseline period) and ≥ 12 months post-index date were selected from the MarketScan Commercial and Medicare Claims database (2005-2009). The index date was defined as the last day of conventional systemic or biologic drug coverage. Discontinuation was defined as no systemic or no biologic treatment for ≥ 12 consecutive months from the last day of systemic or biologic prescription coverage. Patients were classified as having discontinued from a biologic if there was evidence of biologic drug use during the baseline period; otherwise they were defined as having discontinued from non-biologic systemic therapy. Twelve-month average costs following discontinuation were reported. RESULTS: A total of 4,720 psoriasis patients met the selection criteria; 67.4% discontinued from non-biologic systemic therapy and 32.6% from biologic therapy. Over the 12-month period following discontinuation, total costs were $10,577 (SD: 19,910) and $9,001 (SD: 16,401) for biologic and non-biologic discontinuers, respectively (p=0.004).  Outpatient and medication costs were significantly higher for the biologic discontinuers compared to the non-biologic discontinuers ($5,283 vs. $4,449 p= 0.003, and $2,738 vs. $2,470, p= 0.022, respectively). There was no statistically significant difference in hospital/ER costs ($2,556 vs. $2,083, p= 0.214, respectively). Outpatient costs accounted for approximately 50% of total costs for both cohorts.  CONCLUSIONS: This study suggests that outpatient costs account for a substantial proportion of health care costs in psoriasis patients who discontinued from systemic or biologic therapy. Patients who had discontinued from biologic therapy incurred significantly higher outpatient and medication costs compared to patients who had discontinued from conventional systemic therapy.