Depression Pharmacology

Question 1

What are the drugs for depression? (5)

Answer 1

Sertraline
Citalopram
fluoxetine
venlafaxine
mirtazapine

Question 2

What is the drug target of sertraline?

Answer 2

Serotonin transporter

Question 3

What is the mechanism of action of sertraline?

Answer 3

Inhibition of serotonin reuptake results in an accumulation of serotonin. Serotonin in the central nervous system plays a role in the regulation of mood, personality, and wakefulness.

Question 4

What are the main side effects of sertraline?

Answer 4

GI effects (nausea, diarrhoea), sexual dysfunction, anxiety, insomnia

Question 5

What does sertraline also have mild inhibition of?

Answer 5

Mild inhibition of dopamine transporter

Question 6

How should you discontinue sertraline?

Answer 6

Must be gradually decreased on discontinuation. Partial inhibition of CYP2D6 at high doses (150 mg).

Question 7

What is the drug target of citalopram?

Answer 7

Serotonin transporter

Question 8

What is the mechanism of action of citalopram?

Answer 8

Inhibition of serotonin reuptake results in an accumulation of serotonin. Serotonin in the central nervous system plays a role in the regulation of mood, personality, and wakefulness.

Question 9

What are the main side effects of citalopram?

Answer 9

GI effects (nausea, diarrhoea), sexual dysfunction, anxiety, insomnia

Question 10

What mild antagonism does citalopram also have?

Answer 10

Mild antagonism of muscarinic and histamine (H1) receptors

Question 11

How do you stop giving citalopram and what metabolises it?

Answer 11

Must be gradually decreased on discontinuation. Metabolized by CYP2C19.

Question 12

What is the drug target of fluoxetine?

Answer 12

Serotonin transporter

Question 13

What is the mechanism of action of fluoxetine?

Answer 13

Inhibition of serotonin reuptake results in an accumulation of serotonin. Serotonin in the central nervous system plays a role in the regulation of mood, personality, and wakefulness.

Question 14

What are the main side effects of fluoxetine?

Answer 14

GI effects (nausea, diarrhoea), sexual dysfunction, anxiety, insomnia

Question 15

What is fluoxetine also a mild antagonist of?

Answer 15

Mild antagonism of 5HT2A and 5HT2C receptors

Question 16

What does fluoxetine inhibit?

Answer 16

Complete inhibition of CYP2D6 and significant inhibition of CYP2C19 (caution with warfarin).

Question 17

What is the drug target of venlafaxine?

Answer 17

Serotonin transporter

Noradrenaline transporter

Question 18

What is the mechanism of action for venlafaxine?

Answer 18

Venlafaxine is a more potent inhibitor of serotonin reuptake than norepinephrine reuptake.
Noradrenaline in the central nervous system is implicated in the regulation of emotions and cognition.

Question 19

What are the main side effects of venlafaxine?

Answer 19

GI effects (nausea, diarrhoea), sexual dysfunction, anxiety, insomnia, hypertension (at higher doses)

Question 20

What must you do on discontinuation of venlafaxine?

Answer 20

gradual discontinuation

Question 21

What is the drug target for mirtazapine?

Answer 21

Alpha-2 receptor

5-HT2 receptor

Question 22

What is the mechanism of action of mirtazapine?

Answer 22

Antagonises central presynaptic alpha-2-adrenergic receptors, which causes an increased release of serotonin and norepinephrine.
Antagonises central 5HT2 receptors, which leaves 5HT1 receptors unopposed causing anti-depressant effects.

Question 23

What are the side effects of mirtazapine?

Answer 23

Weight gain, sedation

Question 24

What is a possible side effect of mirtazapine?

Answer 24

low probability of sexual dysfunction. May exacerbate REM sleep behaviour disorder

Question 25

What questionnaire can be used to help diagnose depression?

Answer 25

PATIENT HEALTH QUESTIONNAIRE-9 (PHQ-9)

Question 26

What are the types of depression?

Answer 26

mild moderate moderately severe severe

Question 27

Answer 27

Alleviate depressive symptoms: Improve his mood Help with sleep difficulties Improve his self-esteem Improve his ability to think clearly

Question 28

What are the 3 most commonly prescribed SSRIs?

Answer 28

Sertraline Citalopram Fluoxetine

Question 29

What is the mechanism of action of SSRIs?

Answer 29

Selective serotonin reuptake inhibitors (SSRIs)

Question 30

What should you be careful of with citalopram (and erythromycin)?

Answer 30

they both prolong the QT interval most manufacturers advise asvoiding the use of 2 or more drugs that are associated with QT prolongation

Question 31

What are risk factors for predisposed QT interval? (4)

Answer 31

increasing age female sex cardiac disease and some metabolic disturbances (notable hypokalaemia)

Question 32

Answer 32

Dose increase doesn’t really benefit depression improvement, but does worsen side effects the plateau is due to all the 5-HTs already being occupied

Question 33

Answer 33

very basic wise, there isn't enough receptors- like they're fully blocked so can't be reuptaken but cant speed up the uptake

Question 34

What is the drug target type for venlafaxine and mirtazapine, and what are they?

Answer 34

Question 35

Why do you think the GP slowly weaned patients off sertraline first before starting a new anti-depressant?

Answer 35

Caution is required when switching from one antidepressant to another due to the risk of drug interactions, serotonin syndrome, withdrawal symptoms, or relapse. Washout required before starting new drug

Question 36

Answer 36

Adrenergic effects of venlafaxine appear with doses administrated more than 150 mg/day, apparent increase in blood pressure and increased heart rate are observed when the daily dose exceeds 300 mg Mirtazapine modestly suppress REM sleep whilst still having a beneficial impact on sleep continuity and duration due to its anti- histaminergic effects.

Question 37

What are the drug targets of mirtazapine, what are tis effects and what does it have highest affinity for (highest to lowest)?

Answer 37

Question 38

Which effect would be induced first at low dose of mirtazapine?

Answer 38