I.v. temazepam: theoretical and clinical considerations.

Two injectable forms of temazepam, in 90% propylene glycol or 40% salicylic acid, were studied in volunteers, and before surgery in healthy patients. The volunteers also received two forms (capsule and elixir) by mouth. The salicylate preparation was painful on injection and both i.v. formulations caused an unacceptably high incidence of venous thrombosis. Temazepam was detected in plasma earlier following the elixir preparation than the capsule. Plasma concentrations were similar following both injectable preparations. The potency of i.v. temazepam in inducing drowsiness in patients was much less than expected and doses greater than 0.6 mg kg-1 were required to produce adequate sedation. There was a significant reduction in thiopentone induction dose in patients receiving temazepam i.v.