Generalised anxiety Disorder symptoms
- Excessive worrying / nervousness
- Interferes with daily life
- Present for at least 6 months
Other anxiety and fear disorders
- PTSD
- Phobia
- Panic disorders
- OCD
Biochemical state of anxiety
- Sympathetic system is activated -> central and peripheral noradrenergic / adrenergic activation
- Release of stress hormone - activation of HPA
Therapeutic rationale
- Sedatives - relaxation
- Hypnotics - induce sleep / drowsiness
- Anxiolytic - reduces anxiety
Dose dependent usage
low dose = anxiolytics / sedative effects
high dose = hypnotic
higher dose = anasthesia
Name Benzodiazepines and their specific uses
Sedatives / anxiolytics: Diazepam, Lorazepam
Hypnotics: diazepam, triazolam, temazepam
Pre-anasthetics: Diazepam, midazolam
Anticonvulsant: diazepam
MOA of Benzodiazepines
Potentiates GABA actions on GABA receptor - GABA has inhibitory effects in the brain
- Increases frequency of chloride channel opening
- Influx of chlorine -> neuron becomes more negative than surrounding
- Hyperpolarisation - neuron stop firing
Effects:
Limbic system - alters mood
Motor cortex - relax muscles
Reticular activating system - drowsiness
Duration of action of Benzodiazepines
Short-acting: Midazolam, Triazolam
Intermediate-acting: Lorazepam, Temazepam
Long-acting: Diazepam
Adverse effects of Benzodiazepines
- Acute toxicity / overdose - respiratory depression
- Side effects - drowsiness, confusion, amnesia
- tolerance / dependence - withdrawal effects: rebound anxiety, tremor
Name non-diazepams
- Barbiturates
- Busprione
- Zolpidem
- Propranolol
- Pregabalin
- Hydroxyzine
MOA of Zolpidem
Potentiates GABA mediated chloride channel opening - same site as benzodiazepines
- hypnotics effects
- no anxiolytic effects
MOA of Busprione
Partial 5-HT agonist + binds to Dopamine receptors
no anticonvulsant / muscle relaxant properties
MOA of Barbiturates
Potentiates GABA mediated chloride channel opening - different site than benzodiazepines
Anasthetic dose: directly opens Cl- channels + blocks Na+ channel
Adverse effects of barbiturates
Severe withdrawal symptoms
High risk of abuse
Barbiturates duration of action + specific benefit + name of drug
Long acting (1-2days) - Anticonvulsant: Phenobarbital
Short acting (3-8hours) - sedative + hypnotics: Pentobarbital and amobarbital
Ultrashort (20mins) - IV induction anasthesia: thiopental
MOA of Propranolol
Beta-adrenergic antagonist
patients with performance anxiety + social phobia
reduces physical symptoms associated with adrenergic activation
Contraindicated in patients with asthma and heart conditions
MOA of Pregabalin
GABA analogue that increases frequency of chloride channel opening -> hyperpolarisation
Acts on voltage gated calcium channels as well
Treats GAD + anticonvulsant
AE: suicidal thoughts
MOA of Hydroxyzine
First generation antihistamine with effects on serotonergic and alpha-adrenergic receptors
- anxiolytic effects
- helps with itching
