I.v. temazepam: theoretical and clinical considerations.

Area of Science:

• Pharmacology
• Anesthesiology

Background:

• Temazepam is a benzodiazepine used for sedation.
• Investigating novel injectable formulations of temazepam is crucial for optimizing its clinical application.

Purpose of the Study:

• To evaluate the safety and efficacy of two injectable temazepam formulations (propylene glycol and salicylic acid).
• To compare the pharmacokinetic profiles of oral (capsule, elixir) and intravenous (IV) temazepam.
• To assess the sedative potency of IV temazepam and its effect on thiopental induction dose.

Main Methods:

• Volunteers and surgical patients received oral (capsule, elixir) and IV temazepam formulations.
• Plasma concentrations were monitored.
• Sedative effects and thiopental induction doses were recorded.

Main Results:

• The salicylic acid injectable preparation was painful; both IV formulations led to high rates of venous thrombosis.
• Oral elixir showed faster temazepam absorption than capsules.
• IV temazepam exhibited lower-than-expected sedative potency, requiring doses >0.6 mg/kg.
• IV temazepam significantly reduced the thiopental induction dose.

Conclusions:

• Injectable temazepam formulations pose significant safety concerns (pain, thrombosis) and have reduced sedative efficacy.
• Oral elixir provides more rapid absorption compared to capsules.
• IV temazepam can reduce the dose of other anesthetic agents like thiopental.