Buspirone dependence liability

Two studies have indicated that the tricyclic antidepressant (TCA) imipramine may be as effective as BZDs in the treatment of GAD ( 58, 59). No studies longer than 8 weeks duration have been conducted, however, and imipramine s onset of anxiolytic action may be even slower than that of buspirone. Aithough adverse effects also may limit usefulness, its lack of dependence liability may make it an appropriate alternative in chronically anxious patients who also suffer from panic and depression. 

Anxiety disorders are common in the population of opioid-addicted individuals however, treatment studies are lacking. It is uncertain whether the frequency of anxiety disorders contributes to high rates of illicit use of benzodiazepines, which is common in methadone maintenance programs (Ross and Darke 2000). Increased toxicity has been observed when benzodiazepines are co-administered with some opioids (Borron et al. 2002 Caplehorn and Drummer 2002). Although there is an interesting report of clonazepam maintenance treatment for methadone maintenance patients who abuse benzodiazepines, further studies are needed (Bleich et al. 2002). Unfortunately, buspirone, which has low abuse liability, was not effective in an anxiety treatment study in opioid-dependent subjects (McRae et al. 2004). Current clinical practice is to prescribe SSRIs or other antidepressants that have antianxiety actions for these patients. Carefully controlled benzodiazepine prescribing is advocated by some practitioners. 

Azapirones. Though several azapirones have been developed and tested in the laboratory setting, only one, bnspirone (Bnspar), is currently on the market. Buspirone is the first nonsedating, nonbenzodiazepine anxiolytic, other than the antidepressants described earlier. It has no dependence or addictive liability and is not lethal in overdose. Buspirone is also devoid of many of the problems of the benzodiazepines such as sedation, motor impairment, addiction, physical dependence, or withdrawal. Yet, doubts remain in the minds of many practitioners regarding the effectiveness of buspirone. This will be discussed in more detail later in this chapter. 

An additional psychotropic medication that may be worth considering specifically for GAD is buspirone. One major benefit of buspirone can be found in the virtual absence of dependence and abuse liability. Although it is not effective for the acute relief of anxiety or panic disorders (anxiolytic effects may take up to a week to be established), buspirone may be indicated for patients with a history of alcohol abuse or among those who fear physiologic and psychological dependence with benzodiazepines. 

Answer B. Buspirone has selective anxiolytic activity that is slow in onset The drug has no abuse liability and will not suppress withdrawal symptoms in patients who have become physically dependent on barbiturates, benzodiazepines, or ethanol. Bupropion is an antidepressant, also approved for management of dependence on nicotine. Baclofen is a spinal cord muscle relaxant that activates GABAfi receptors. Buprenorphine is a long-acting opioid analgesic with no effectiveness in GAD, and butabarbital is a barbiturate that may cause dependence. 

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