A flow-injection manifold is proposed for the determination of epinephrine. The experimental procedure is based on the indirect biamperometric detection of the drug by using Fe(III)-Fe(II) as an indicating redox system and a flow-through detector with two polarized Pt wire electrodes. The calibration graph is linear over the range 0.3-20 mu g ml(-1) of epinephrine. The relative standard deviation for the determination of 10 mu g ml(-1) of epinephrine is 1.5% (n = 25) and the sample throughput is 153 h(-1). The method was applied to the determination of epinephrine in two commercially available pharmaceutical preparations. (C) 1997 Elsevier Science B.V.