Anxiolytics development

The CCK system shares one property with the opioid system, ie, the existence of selective nonpeptide antagonists. These include aspedicine, a natural benzodiazepine (136), and Devazepide (L-364,718 MK-329) (137). Selective, potent peptide antagonists for CCK, eg, Cl-988 and PD 134308, have been developed that maybe useful as anxiolytics and as dmgs which increase the analgesic effect of morphine but at the same time prevent morphine tolerance (138) (see Hypnotics, sedatives, anticonvulsants, and anxiolytics). 

Anxiolytics are drugs used for the treatment of anxiety disorders. Apart from benzodiazpines, a frequently used anxiolytic is the 5HT1A (serotonin) receptor agonist buspiron, which has no sedative, amnestic or muscle-relaxant side effects, but whose action takes about a week to develop. Furthermore, it is less efficaceous than the benzodiazepines. Buspiron s mechanism of action is not fully understood. 

Psychiatric adverse effects occur frequently and may include irritability, depression, and rarely, suicidal ideation. Individuals with a history of uncontrolled psychiatric disorders must weigh the risk versus benefit of treatment, as interferon may exacerbate or worsen the psychiatric condition. Patients who develop mild to moderate symptoms may require antidepressants or anxiolytics. Those with severe symptoms including suicidal ideation should have the treatment discontinued immediately.43... 

Yamawaki, S. (1999). The use and development of anxiolytics in Japan. Eur. Neuropsychopharmacol, 9(suppl 6), S413-S419. 

Sandler M (1992). Development of anxiolytic and antidepressant drugs A historical perspective. In JM Elliot, DJ Heal and CA Marsden (eds), Experimental Approaches to Anxiety and Depression (pp. 1-8). John Wiley Sons, Chichester, UK. 

The answer is d. (Hardman, p 564.) A long-acting benzodiazepine, such as diazepam, is effective in blocking the secobarbital withdrawal symptoms. The anxiolytic effects of bus pi rone take several days to develop, obviating its use for acute severe anxiety... 

Ultrasonic vocalizations are emitted by rat pups (under the age of 14 days) when they are isolated from their mother, and are thought to reflect anxiety. This measure has proven sensitive to both anxiolytic and anxiogenic manipulation of GABA neurotransmission. However, the early developmental window used is problematic, in that chronic drug administration probably results in a variety of compensatory changes not seen in adulthood, and may alter development of relevant brain systems. Indeed, in contrast to the clinical situation, the antidepressant clomipramine has acute, but not chronic, anxiolytic efficacy in this model. 

Another SNRI, bicifadine (20), formerly under clinical development for chronic low back pain, is now being developed for neuropathic pain [65,66]. Flufenoxine, also known as F-98214-TA (21), was reported to display greater potency than several reference antidepressants in animal models predictive of antidepressant and anxiolytic activities [67]. SEP-227162 (structure undisclosed) is another SNRI reportedly undergoing clinical development [68]. 

Catania MA, Firenzuoli F, Crupi A, Mannucd C, Caputi AP, Calapai G (2003) Hypericum perforatum attenuates nicotine withdrawal signs in mice. Psychopharmacology 169 186-189 Cheeta S, Irvine EE, Kenny PJ, File SE (2001) The dorsal raphd nucleus is a crucial structure mediating nicotine s anxiolytic effects and the development of tolerance and withdrawal responses. Psychopharmacology 155 78-85... 

Monoamine Oxidase inhibitors (MAOis). Developed in the 1950s, the MAOIs were the first class of antidepressants. Subsequently, in the 1960s, the MAOis were also found to be effective anxiolytics. Unlike benzodiazepines and barbiturates, the MAOis are not addictive however, their onset of action is delayed not by minutes or hours but by 3 weeks or more. 

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. 

In addition to the benzodiazepine receptor agonists which, depending on the dose administered, have anxiolytic, anticonvulsant, sedative and amnestic properties, benzodiazepines have also been developed which block the action of agonists on this receptor. Such antagonists may be exemplified by... 

In SUMMARY, it would appear that a detailed knowledge of the pharmacokinetics of the main groups of psychotropic drugs is only of very limited clinical use. This is due to limitations in the methods for the detection of some drugs (e.g. the neuroleptics), the presence of active metabolites which make an important contribution to the therapeutic effect, particularly after chronic administration (e.g. many antidepressants, neuroleptics and anxiolytics), and the lack of a direct correlation between the plasma concentration of the drug and its therapeutic effect. Perhaps the only real advances will be made in this area with the development of brain imaging techniques whereby the concentrations of the active drug in the... 

The development of the benzodiazepine class of drugs for the treatment of a variety of neurological indications has proven to be an outstanting success story in the field of chemotherapy. However, these compounds often produce undesirable side effects when used as anti-anxiety or hypnotic agents. These side effects include sedation, physical dependence, amnesia, muscle relaxation, and ethanol potentiation. The development of a benzodiazepine receptor-based anxiolytic agent devoid of these side effects would constitute a major advance in the field and has been the focus of significant research efforts [284]. 

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