The aim of this double-blind, placebo-controlled cross-over design trial was to assess the safety of a multi-vitamin preparation containing nicotinic acid in a physiological dose. Seventy-two healthy volunteers took part in this trial. At six consecutive time-points, we systematically documented blood pressure, pulse, skin temperature and flushing symptoms after an oral dose of up to 50.1 mg nicotinic acid. The results suggest that nicotinic acid in a dosage of 16.7 mg does not cause flushing symptoms. In higher doses up to 50.1 mg, flushing symptoms are sporadically possible. There was no physiologically relevant change regarding the central metabolic parameters blood pressure, pulse and skin temperature.