24. Anxiety and anxiolytics Flashcards
What are the different types of anxiety disorders?
Panic disorder Agoraphobia Social phobia - social anxiety disorder Simple phobia Obsessive compulsive disorder Post-traumatic stress disorder Generalised anxiety disorder
Which neurological structures are involved in anxiety disorders?
Amygdala - involved in the control of fear and anxiety potentially thought to be perceived as a type of fear
HPA axis - some abnormalities in the stress response
Which neurotransmitters are involved in anxiety disorders?
Monoaminergic systems (5-HT, dopamine) GABAergic systems
Explain the role of the amydala in anxiety
There is a hyperactivity of the limbic structures i.e. the amygdala and there is an accompanied inability of cortical structures to control this hyperactivity
What are the different types of anxiolytics and give specific examples?
Benzodiazepines - clonazepam, alprazolam
5-HT1a agonists e.g. buspirone, ipsapirone
B-adrenoreceptor antagonist e.g. propranolol
SSRIs e.g. fluoxetine, escitalopram, paroxetine
What are barbiturates?
These are anxiolytics which are no longer used as they were associated with a lot of issues
These were positive allosteric modulators at the GABAa receptors and they caused these channels to remain open for longer
What were the issues associated with barbiturates?
Very strong CNS depressants so many adverse effects
Major risk of drug dependence
Development of tolerance
Fatal toxicity in overdose - respiratory depression
Accumulation causes drowsiness, disorientation, ataxia, slurred speech
At what receptor do benzodiazepines have an effect?
These are positive allosteric modulators at GABAa receptors
These cause the channels to open more frequently than normal
How is benzodiazepine overdose managed?
Flumazenil
This acts as an antagonist at the benzodiazepine binding sites
Has a short half life
What are the complications of benzodiazepine use in the elderly?
Psychomotor impairment Risk of falls Daytime drowsiness Intoxication Amnesia Depression Respiratory problems Abuse and dependancy