Generalized anxiety mechanisms

Buspirone Mechanism uncertain Partial agonist at 5-HT receptors but affinity for D2 receptors also possible Slow onset (1-2 weeks) of anxiolytic effects t minimal psychomotor impairment—no additive CNS depression with sedative-hypnotic drugs Generalized anxiety states Oral activity forms active metabolite short half-life Toxicity Tachycardia paresthesias t gastrointestinal distress Interactions CYP3A4 inducers and inhibitors... 

In addition to its efficacy as a first-line antidepressant, mirtazapine may have enhanced efficacy due to its dual mechanism of action (Fig. 7—3), especially in combination with other antidepressants that block serotonin and/or norepinephrine reuptake. This will be discussed below in the section on antidepressant combinations. Mirtazapine may also have utility in panic disorder, generalized anxiety disorder, and other anxiety disorders, but has not been intensively studied for these indications. 

The serotonin 1A partial agonist buspirone, whose primary use is in generalized anxiety disorder, is also used as a popular augmenting agent for treatment-resistant depression, particularly in North America (serotonin 1A combo in Fig. 7—30). Its potential mechanism of action as an antidepressant augmenting agent is shown in Figures 7—31 to 7—33. 

Nutt, D. J. (2001). Neurobiological mechanisms in generalized anxiety disorder. J. Clin. Psychiatry, 62 Suppl 11, 22-7 discussion 28. 

Buspirone (and tandospirone in Japan) are the only non-selective serotonergic medications presently approved for the treatment of generalized anxiety disorder (GAD) in many countries, including the USA. They have a relatively unique mechanism of action (i.e. being... 

Modulation of GABA receptors is also beneficial in the treatment of several neuropsychiatric conditions, including anxiety disorders, insomnia, and agitation. The mechanisms are not well understood but may work through a general inhibition of neuronal activity. Benzodiazepines and ethanol use the same mechanism to influence GABA receptors. This property is the basis for ethanol detoxification with benzodiazepines (Grobin et ah, 1998). 

The mechanism of action and chnical use of domperidone and its specific use in diabetic gastroparesis have been reviewed (5,6). Domperidone is generally well tolerated and has a low incidence of adverse effects. Adverse effects after oral administration include headache, dry mouth, diarrhea, itching, muscle cramps, and anxiety. Galactorrhea, breast tenderness, and pseudopregnancy can occur in women because of a dopamine-induced increase in serum prolactin concentration. 

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