The respiratory effects of oral ethyl loflazepate in volunteers.

A volunteer study was undertaken to assess the respiratory effects of ethyl loflazepate, a new benzodiazepine, and to correlate these with plasma concentrations of the active metabolites. Twelve volunteers were given placebo, 2 mg ethyl loflazepate, and 6 mg ethyl loflazepate on separate occasions. Respiration and plasma metabolite levels were assessed hourly for 8 h and at 24 h. The 6 mg ethyl loflazepate treatment produced a significant decrease (P less than 0.02) in the ventilatory response to carbon dioxide at 5 h. However this did not equate with a peak in plasma metabolite concentrations which were maintained at a plateau level from 4 to 24 h.