Pharmacology of antidepressants and mood stabilisers

Question 1

What properties do drugs need to have to pass through the BBB?

Answer 1

Lipophilic/ hydrophobic

Question 2

What are the clinical uses of antidepressants?

Answer 2

Moderate to severe depression 
Dysthymia
Generalised anxiety disorder
Panic disorder
OCD
PTSD
Premenstrual dysphoric disorder
Bulimia nervosa
Neuropathic pain

Question 3

What are the different types of antidepressant drugs?

Answer 3

Monoamine oxidase inhibitors
Monoamine reuptake inhibitors; tricyclics, non-selective reuptake inhibitors, SSRIs, NA reuptake inhibitors
Atypical; post-synaptic receptor effects

Question 4

What are the monoamine neurotransmitters involved in depression?

Answer 4

NA
5-HT
Dopamine

Question 5

Is there an excess or deficit of monoamine nTs in depression?

Answer 5

Deficit

Question 6

What is 5-HT involved in within the brain?

Answer 6

Mood
Sleep
Feeding behaviour
Sensory perception 
Analgesia

Question 7

What is the base amino acid of serotonin?

Answer 7

Tryptophan

Question 8

What enzyme will break up 5-HT into 5-HIAA?

Answer 8

MAO

Question 9

What are example of monoamine oxidase inhibitors?

Answer 9

Phenelzine

Moclobemide

Question 10

What are the side effects of monoamine oxidase inhibitors?

Answer 10

Hypertensive crisis due to lack of breakdown of tyramine
Potentiates other drugs such as barbiturates
Insomnia
Postural hypotension
Peripheral oedema

Question 11

Examples of tricyclic antidepressants

Answer 11

Imipramine
Dosulepin
Amitriptyline
Lofepramine

Question 12

What is the mode of action of tricyclic antidepressants?

Answer 12

Block reuptake of monoamines (mainly NA and 5-HT) into presynaptic terminals

Question 13

What are common side effects of tricyclic antidepressants?

Answer 13

Anticholinergic; blurred vision, dry mouth, constipation, urinary retention
Sedation 
Wt gain
CV; postural hypotension, tachycardia
Cardiotoxic in overdose

Question 14

Should you give a tricyclic to someone who has ischaemia heart disease or a recent MI?

Answer 14

No

Question 15

Examples of SSRIs?

Answer 15

Fluoxetine
Citalopram
Escitalopram
Sertraline

Question 16

Common side effects of SSRIs?

Answer 16

Nausea
Headache
Sweating
Vivid dreams
Worsened anxiety
Sexual dysfunction 
Hyponatraemia
Transient increase in self-harm/ suicidal ideation in <25 years
Discontinuation effects

Question 17

What is the mode of action of SSRIs?

Answer 17

Selectively inhibit reuptake of serotonin from the synaptic cleft

Question 18

What is the mode of action of mirtazapine?

Answer 18

Blocks alpha, 5-HT2 and 5-HT3 receptors

Question 19

SE of mirtzapine

Answer 19

Wt gain

Sedation

Question 20

What is an example of a dopamine uptake inhibitor?

Answer 20

Bupropion

Question 21

Should antidepressants be used in mild depression?

Answer 21

No - large placebo response

Question 22

What is the caution of prescribing antidepressants in young adults/ teenagers?

Answer 22

Transient increase in suicidal ideation

Aggressive ideas

Question 23

What is the goals of acute treatment in bipolar?

Answer 23

Reduce mood in mania

Increase mood in depression

Question 24

What is the goal of long term treatment in bipolar disorder?

Answer 24

Stabilise mood and prevent recurrence of both mania and depression (prophylaxis)

Question 25

What is the mode of action of lithium as a mood stabiliser?

Answer 25

Blocks phosphatidylinositol pathway (second messenger system) or inhibit glycogen synthase kinase 3-beta

Question 26

Does lithium require therapeutic monitoring?

Answer 26

Yes; 12 hour post dose levels must be monitored due to narrow therapeutic index

Question 27

Common side effects of lithium that occur at therapeutic levels?

Answer 27

``` Dry mouth/ strange taste Polydipsia and polyuria Tremor Hypothyroidism Long term reduced renal function Nephrogenic diabetes insipidus Wt gain ```

Question 28

What are the toxic effects of lithium overdose?

Answer 28

``` Vomiting Diarrhoea Ataxia Drowsiness Convulsions Coma ```

Question 29

Which anticonvulsants are used as mood stabilisers in bipolar?

Answer 29

Valproic acid Lamotrigine Carbamazepine

Question 30

What are the SE of valproate and carbamazepine?

Answer 30

Drowsiness Ataxia CV effects Induces liver enzymes

Question 31

Can valproate be given in pregnancy?

Answer 31

No; neural tube defects

Question 32

What is the risk with lamotrigine?

Answer 32

SJS

Question 33

Which antipsychotics can be given as mood stabilisers?

Answer 33

Quetiapine Aripiprazole Olanzapine Lurasidone

Question 34

What is the mode of action of antipsychotics?

Answer 34

Dopamine antagonism + 5-HT antagonism

Question 35

SE of antipsychotics?

Answer 35

Sedation Wt gain Metabolic syndrome Aripiprazole; extra-pyramidal SE