Abstract
In recent years generalised anxiety disorder (GAD) has become a much better defined disorder, with specific criteria distinguishing it from the other anxiety disorders; however, it still lacks the same public and scientific interests as some of the other anxiety disorders such as panic and social phobia. Nevertheless, refinement in the treatment of GAD is becoming more evident through the conduct of clinical trials.
Up until the mid-1980’s, treatment consisted primarily of benzodiazepines. However, as a result of growing characterisation of their abuse potential, other therapeutic options were explored. Benzodiazepines became seen as an effective short-term therapy, and buspirone and some of the newer antidepressants have become the treatment of choice for patients with GAD requiring long-term treatment.
Buspirone was the first available alternative to the benzodiazepines in the US; however, the initial excitement over this agent was somewhat dampened because of its mild efficacy combined with a slow onset of action. The antidepressants were seen as beneficial for the treatment of GAD because of the high comorbidity with depression, thus allowing a better outcome for these patients. The antidepressants that offer both a good adverse effect profile and efficacy are the selective serotonin reuptake inhibitors including paroxetine, and the serotonin-norepinephrine reuptake inhibitors such as venlafaxine. Clinicians should also consider the potential benefits of psychotherapy as an adjunct to medication.
There are a number of potentially new pharmacotherapies being investigated, including newer serotonin 5-HT1A receptor agonists, cholecystokinin receptor antagonists, neurokinin receptor antagonists, gabapentin and its analogues, and γ-aminobutyric acid (GABA)A receptor modulators. However, these compounds are all in the early stages of investigation, and there are no new therapies expected to be released in the near future. Nonetheless, in the search for the ideal anxiolytic, a more positive outlook is allowed by imminent future research for new treatment options in patients with GAD.
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Sramek, J.J., Zarotsky, V. & Cutler, N.R. Generalised Anxiety Disorder. Drugs 62, 1635–1648 (2002). https://doi.org/10.2165/00003495-200262110-00005
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DOI: https://doi.org/10.2165/00003495-200262110-00005