The contribution of pharmacokinetics to the best use of benzodiazepines and antidepressants.
The practical utilization of clinical pharmacokinetics data are fundamentally different for benzodiazepines and antidepressants. This difference is a consequence of the difference in time-course of action of the two types of drugs. The anxiolytic, sedative or hypnotic effect of benzodiazepines is usually immediate, and the dose can be titrated on the basis of effect measurements. Pharmacokinetic data on benzodiazepines thus in particular are important for design of dose, dose intervals and prediction (warning) about possible accumulation after repeated doses. Different benzodiazepines differ in pharmacokinetic properties, and the clinician should be aware of these differences in order to select the proper drug for a given purpose. Antidepressants are characterized by exerting their effect gradually ovec weeks. It has been shown that the therapeutic effect is related to the steady state plasma concentration which may vary considerably among patients on a standard dose. A major significance of pharmacokinetics of antidepressants thus is, that therapy guided by monitoring of plasma levels of active compounds will improve both safety and efficacy of the treatment. For antidepressants and for benzodiazepines knowledge of the pharmacokinetics is the basis of designing rational dose schedules that take influencing factors such as age, disease, concurrent treatment, etc. into account.
D000639:Amitriptyline / Q000097:blood; D014151:Anti-Anxiety Agents / Q000097:blood*; D000929:Antidepressive Agents, Tricyclic / Q000097:blood*; D001569:Benzodiazepines; D003866:Depressive Disorder / Q000097:blood* / Q000188:drug therapy; D006207:Half-Life; D006801:Humans; D007099:Imipramine / Q000097:blood; D007700:Kinetics; D008657:Metabolic Clearance Rate; D009661:Nortriptyline / Q000097:blood
D014151:Anti-Anxiety Agents; D000929:Antidepressive Agents, Tricyclic; D001569:Benzodiazepines; D000639:Amitriptyline; D009661:Nortriptyline; D007099:Imipramine