Pharmacology of Anxiolytic Drugs

Question 1

What is the general overall mechanism of benzodiazepines?

Answer 1

Act at GABA-A receptor to increase action of GABA causing an inhibitory effect

Question 2

List the pharmacological clinical effects of benzodiazepines

Answer 2

Reduce anxiety and aggression
Hypnosis, sedation
Muscle relaxation
Anticonvulsant effect
Anterograde amnesia

Question 3

Which BZD acts as a GABA receptor antagonist and what is its effect on anxiety?

Answer 3

Flumazenil

Increases anxiety

Question 4

Some people can develop tolerance to BZD’s - what is the significance of this? How long should BZDs be used for?

Answer 4

The doses that work for them can be lethal in normal people

2-4 weeks

Question 5

List the clinical effects of rapid withdrawal of BZD’s

Answer 5

Confusion, psychosis
Convulsions
Tachycardia, sweating, hypertension
Agitation, tremor

Question 6

List drugs used to treat anxiety

Answer 6

Benzodiazepines
Antidepressants (SSRIs, TCADs, SNRIs, MAOI)
Buspirone
Pregabalin
B blockers (propranalol)

Question 7

What is the effect of GABA on the receptor?

Answer 7

Has a positive allosteric effect

Neurone less likely to fire action potential in amygdala and CSTC circuit

Question 8

Which part of the brain has a role in controlling fear?

Answer 8

Amygdala

Question 9

Which part of the brain has a role in controlling worry?

Answer 9

Cortico-striato-thalamo circuit

Question 10

How long should benzodiazepines be used for? Why?

Answer 10

2-4 weeks maximum due to issue of dependance

Chronic treatment leads to reduced response to GABA and possibly increased anxiety

Question 11

Give examples of the main benzodiazepines used clinically

Answer 11

Lorazepam
Diazepam
Chlordiazepoxide
(Have different durations of action on GABA receptor)

Question 12

List other clinical uses of bezodiazepines, aside from anxiety

Answer 12

Alcohol withdrawal
Mania
Delirium
Status epilepticus

Question 13

List features of benzodiazepine withdrawal

Answer 13

Abdominal cramps
Anxiety, panic attacks
Muscle tension, chest pain, palpitations, sweating, shaking
Blurred vision
Depression, insomnia, nightmares
Dizziness, headaches, inability to concentrate
Nausea, vomiting
Tingling in hands and feet, sensory sensitivity
Restlessness

Question 14

How should benzodiazepines be withdrawn safely?

Answer 14

Transfer to daily dose taken at night
Reduce dose every 2-3 weeks by small amounts
Stop completely, withdrawal from 4wks - 1yr

Question 15

Propranolol is useful for treating what type of symptoms in anxiety?

Answer 15

Somatic symptoms - palpitation, tremor

Question 16

Outline the six management options for GAD, starting with 1st line

Answer 16

1. Psychoeducation
2. Self-help and group sessions
3. High intensity psychological treatment (CBT) or drug treatment (SSRI, benzodiazepines in ST)
4. SNRI
5. Pregabalin
6. Combo of CBT and drugs

Question 17

Drug treatment for GAD should be tried for _____ and continued for _____

Answer 17

12 weeks

18 months

Question 18

Outline the three management options for panic disorder, starting with 1st line

Answer 18

1. Self-help
2. CBT or SSRI if LT or no response to CBT
3. TCADs (clomipramine, desipramine, imipramine, tofepramine)

Question 19

Which drugs should be avoided in panic disorder?

Answer 19

Benzodiazepines
Sedating antihistamines
Propranalol
Buspirone
Buprapion

Question 20

Outline the six management options for OCD, starting with 1st line

Answer 20

1. Low intensity psychological treatment (CBT, ERP, self-help)
2. High intensity psychological treatment or SSRI (fluoxetine, paroxetine, sertraline, citalopram for 1yr)
3. Consider increasing dose after 4-6 weeks
4. SSRI + CBT + ERP
5. Clomipramine
6. Augmentation with antipsychotic or clomipramine + citalopram

Question 21

Outline the four management options for PTSD, starting with 1st line

Answer 21

1. Mild + <4 weeks from trauma = watchful waiting
2. Within 3 months of trauma = brief psychological intervention (trauma focused CBT) and hypnotic meds for sleep disturbance
3. > 3 months after trauma = trauma focused CBT or EMDR
4. Drugs - paroxetine or mirtazepine
   amitryptiline or phenelzine (MH specialist)

Question 22

Outline the five management options for social anxiety, starting with 1st line

Answer 22

1. Individual CBT
2. SSRI (escitalopram or sertraline) - review at 12 weeks
3. SSRI + CBT
4. Alternative SSRI (fluvoxamine or paroxetine) or SNRI (venlafaxine)
5. MAOI inhibitor (moclebemide)