Our review confirms the usefulness of long-term pharmacological treatments for PD and GAD and suggests that they can provide further improvement over that obtained during short-term therapy .
Paroxetine , escitalopram , and clonazepam can be effective for long-term treatment of PD .
Pregabalin and quetiapine can be effective for long-term treatment of GAD , while preliminary suggestions emerged for agomelatine and vortioxetine .
We did not find any evidence for determining the optimal length and /or dosage of medications to minimize the relapse risk .
Many aspects of long-term pharmacological treatments for  anxiety disorders ( AnxDs ) are still debated .
We undertook an up date d systematic review of long-term pharmacological studies on panic disorder ( PD ) , generalized anxiety disorder ( GAD ) , and social anxiety disorder ( SAD ) .
Variation in the catechol-O-methyltransferase (COMT) gene and treatment response to venlafaxine XR in generalized anxiety disorder
Antidepressant drugs are the preferred choice for the treatment of generalized anxiety disorder ( GAD ) . However , the choice of pharmacotherapy is determined on a trial- and -error basis , as the underlying mechanisms of treatment response are unknown . We examined whether the COMT gene , which has been known to play a role in antidepressant treatment response in major depressive disorder ( MDD ) , has a pharmacogenetic effect in antidepressant treatment response in GAD . In our study , 156 patients diagnosed with GAD received venlafaxine XR treatment as part of an 18-month relapse prevention study . Genotypes were obtained for the COMT functional variant rs4680 ( Val158Met ) for all patients ; however , pharmacogenetic analysis was only conducted for the European American population ( n=112 ) . We found no significant association between our primary Hamilton Anxiety Scale outcome measure and rs4680 . However , we did find a nominally significant allelic association between this variant and a secondary treatment outcome measure ( CGI-I ) in our European American population ( n=112 ) . Furthermore , we show a slight dominant effect of the A-allele with the CGI-I measure in the European American population indicating a possible pharmacogenetic role of rs4680 in antidepressant treatment outcome in GAD . Further studies in a larger population are needed to confirm this effect
Our review confirms the usefulness of long-term pharmacological treatments for PD and GAD and suggests that they can provide further improvement over that obtained during short-term therapy .
Paroxetine , escitalopram , and clonazepam can be effective for long-term treatment of PD .
Pregabalin and quetiapine can be effective for long-term treatment of GAD , while preliminary suggestions emerged for agomelatine and vortioxetine .
We did not find any evidence for determining the optimal length and /or dosage of medications to minimize the relapse risk .
Many aspects of long-term pharmacological treatments for  anxiety disorders ( AnxDs ) are still debated .
We undertook an up date d systematic review of long-term pharmacological studies on panic disorder ( PD ) , generalized anxiety disorder ( GAD ) , and social anxiety disorder ( SAD ) .