[Clinical pilot study of the myogenic effects of flupirtine in comparison to tetrazepam and placebo].

The effects of flupirtine (CAS 56995-20-1, D-9998, Katadolon) on muscle force and related electromyographic (EMG) activity has been assessed in comparison to tetrazepam and placebo in 12 healthy male volunteers after oral single-dose administration and under steady-state conditions. Muscle functions primarily reflecting dynamic daily demands remained unaffected under flupirtine in contrast to tetrazepam, the latter exhibiting the typical signs of increased (co-)innervation which can be interpreted as a compensation of a decrease of muscle force. Under conditions that serve as a model for static-spastic situations, flupirtine showed a decrease, tetrazepam a typical increase in the force parameter. Under the same conditions, a decrease of the EMG-amplitude was observed for flupirtine and, to a lesser extent, for tetrazepam as well. With respect to its muscle relaxing property, flupirtine differs both, quantitatively and qualitatively from tetrazepam, which has shown effects common for benzodiazepines.