Anxiolytics and Hypnotics

Question 1

What is anxiety?

Answer 1

One of the most common human emotions. Associated with perception/anticipation of a danger threatening the integrity, security, well being and self esteem of the individual.

Normal - stressful situation
Pathological - prolonged and severe. Occurs without a stressful event, interferes with normal life. Associated with illness/depression/personality disorders. Clinical condition; phobic anxiety/panic disorder.

Question 2

What is pathological anxiety?

Answer 2

Exaggerated fear state, hyperexcitability of fear circuits that include the amygdala and expressed as hypervigilance and increased behavioural responsitivty to fearful stimuli.

Question 3

What are the 2 major manifestations of anxiety

Answer 3

1) Somatic and autonomic effects - restlessness/agitation/insomnia
2) Psychological symptoms - irritability, insomnia and inability to concentrate.

Question 4

Explain pre clinical testing involved with anxiety?

Answer 4

Anxiety occus in a particular form of behavioural inhibition in response to events that are novel, non-rewarding or punishing.

Rats eater bottle - electrically wired. Normally mouse wouldn’t drink. BDZ and mice drinks.

Question 5

What are the 4 classes of anxiolytic drugs?

Answer 5

Benzodiazepines
5HT1A receptor agonist
Barbituates
B-adrenergic antagonists

Question 6

Explain how benzodiazepines work.

Answer 6

diazepam.
Anticonvulsant
Decrease anxiety and aggression.
Sedative and hypnotic
Decreases muscle tone.

Potentiates the effect of GABA by facilitating the opening of GABAa activated Cl- channels.

Accumulates in fat.
Excreted as glucouronides.

Question 7

What acute toxicity is associated with BDZ use?

Answer 7

Overdose: prolonged sleep without serious depression of resp/CV funcitons.
If BDZ and ALCOHOL - severe respiratory depression
Overdose treated with a BDZ antagonist - flumazenil.

Question 8

Side effects of BDZ?

Answer 8

Drowsiness, confusion, amnesia, impaired coordination.
If as hypnotic - day after impairment of job performance and driving skills.

Induces tolerance and physical dependence.

Question 9

Explain 5HT1A agonists.

Answer 9

Buspirone.
act on inhibitory pre synaptic receptors inhibiting seretonin release.
Take weeks to have efficacy.
Not used for panic attacks.
Side effects - nausea, dizziness, headache and restlessness.

Question 10

Explain barbituates

Answer 10

Hypnotics, sedatives, CNS depression…in large doses can cause death from CV and respiratory depression.

Phentobarbitone - hypnotic, anxiolytic
Phenobaritone - anticonvulsant
Thiopentone - anaesthetic

They enhance the action of GABA - less specific that BDZ.
Induce tolerance, dependence, and increase metabolic degradation of other drugs.