The efficiency of prescribing HA-1A for sepsis patients is analysed by comparing direct medical costs and effects. Effects are estimated on the basis of published data from a randomised clinical trial. Costs are analysed by combining data from the same trial with expectations about hospital days. Average costs per life year gained are estimated at DF1. 25,000. Sensitivity analysis is applied and the efficiency of treating patients with HA1A is shown to depend highly on the expected duration of survival after successful treatment. This leads to the advice to take epidemiologic knowledge into special account before setting the indication for using HA-1A.