Efficacy in Treating Symptoms
Anxiety symptoms respond well to BZs such as lorazepam (Ativan), clonazepam (Klonopin), chlordiazepoxide (Librium), diazepam (Valium), and alprazolam (Xanax). However, if it is expected that the symptoms will require treatment for more than several weeks, antidepressants or buspirone (BuSpar) will become the first drugs of choice. BZs can be used on an as-needed basis or only for the first several weeks until the antidepressant or buspirone takes effect because of the possible development of dependence on BZs.
Among the antidepressants used for anxiety, serotonergic agents such as paroxetine (Paxil), fluoxetine (Prozac), sertraline (Zoloft), and fluvoxamine (Luvox) are thought to be the best choices as primary medications for long-term treatment of most anxiety symptoms. Other medications for anxiety include some beta-adrenergic blockers such as propranolol (Inderal) or anticonvulsants such as gabapentin (Neurontin) (Pollack, Mathews, & Scott, 1998).
BZs used as central nervous system (CNS) depressants reduce anxiety (anxiolytic effect) at lower doses and produce sedative effects at slightly higher doses. Most BZs also induce sleep (hypnotic effect) at higher doses. However, unlike the case with barbiturates, the central nervous system depressant effect of BZs does not increase to cause coma or death, even if the doses are further increased, as long as they are not used with other CNS depressants such as alcohol.
BZs generally have rapid onsets (i.e., 15–60 minutes after oral administration) except temazepam (Restoril) which may take 45 to 120 minutes to begin taking effect. The long half-life (48–150 hours) of flurazepam (Dalmane) is associated with morning hangover.