OBJECTIVES: Evaluation of real-life dosing of biologics in plaque psoriasis in Germany and the potential savings by treating patients with ustekinumab instead of using higher doses of TNF-alpha-inhibitors.  METHODS: Based on an online survey among 100 dermatologists (DocCheck Medical Services, December 2009) the use of biologics and their dosing distribution for the treatment of plaque psoriasis was evaluated. The proportion of patients receiving maintenance dosages according to label and those receiving a higher dose were evaluated for each biologic separately. A budget impact model was created estimating potential savings by treating patients with ustekinumab according to label (45mg in patients ≤ 100kg body weight and 90mg in patients > 100kg body weight) instead of high dose TNF-alpha-inhibitors in terms of annual medication costs. In this model, costs of the current usage pattern of biologics were estimated using German pharmacy prices (source: Lauer-Taxe, version June 1, 2010, most economical pack size).    RESULTS: In most cases biologic treatments are used according to the respective labels. In some instances, deviating dosages are used: 14% of adalimumab-treated patients receive an increased dosage of 40mg every week or 80 mg eow, and more than 15% of etanercept-treated patients receive 50mg twice weekly or another deviating dosage as maintenance therapy. 27% of infliximab-treated patients receive maintenance injections more frequently than every 8 weeks or receive an increased dosage per injection. In Germany, assuming 80% of those high-dose-TNF-alpha-inhibitor-treated patients are treated with ustekinumab instead, this would result in savings of approximately €18 million per year. If induction costs of ustekinumab are considered additionally, still €13 million could be saved within one year. CONCLUSIONS: Using ustekinumab instead of high dosages of TNF-alpha-inhibitors for treatment of plaque psoriasis can generate significant savings in medication costs in Germany.