pharmacology depression

Question 1

What do you need for diagnosis of depression? What screening tool is used?

Answer 1

Patient health questionnaire 9 (PHQ-9).
Need to show anhedonia & feeling depressed & 3 of following 7. if for period of 2 weeks can be diagnosed with depression soley by using this screening tool

Question 2

What is therapeutic objective for depression?

Answer 2

Make mood less depressed, work on self-esteem

Question 3

What are some commonly prescribed SSRIs?

Answer 3

Sertraline, citalopram, fluoxetine

Question 4

What can citalopram do and what can it interact with?

Answer 4

QT-prolongation. Erythromycin can also cause QT prolongation, avoid use of 2 or more drugs prolonging QT

Question 5

What predisposes to QT-prolongation?

Answer 5

Increasing age, female, cardiac disease & metabolic disturbances (hypokalaemia)

Question 6

What can fluoxetine cause potentially?

Answer 6

cardiac problems

Question 7

What dose for each SSRI? Why not a higher dose?

Answer 7

Fluoxetine 20mg, citalopram & sertraline 50mg. Higher dose increases side effects & reduces effects (plateau) because serotonin levels cant increase any more (saturated)

Question 8

If changing depression drugs what should you do and why?

Answer 8

Slowly taper dose of first drug before stopping it and wait period before starting new drug because can get rebound effect or serotonin syndrome (too much around)

Question 9

What can venlafaxine contribute to and why?

Answer 9

Hypertension because noradrenaline mediates SNS effects on heart worsening hypertension

Question 10

How can mirtazapine help? Where does it have effects?

Answer 10

Can help with sedation by binding on histamine receptors which contribute to sedation. Anti-emetic effects by 5HT3 receptor

Question 11

What are the mechanisms of SSRI drugs?

Answer 11

Inhibition of serotonin reuptake resulting in accumulation of serotonin in synapse.

Question 12

What is role of serotonin?

Answer 12

Regulation of mood, personality, wakefulness

Question 13

What are targets of SSRI drugs?

Answer 13

Serotonin transporter

Question 14

What are side effects of SSRI drugs?

Answer 14

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

Question 15

Where else does sertraline have effects?

Answer 15

Mild inhibition of dopamine transporter

Question 16

Where else does citalopram have effects?

Answer 16

Mild antagonism of muscarinic and histamine H1 receptors

Question 17

Where else does fluoxetine have effects? What should you be careful giving it with?

Answer 17

Mild antagonism of 5HT2A & 5GT2C receptors. Complete inhibition of CYP2D6 and significant inhibition of CYP2C19 (caution with warfarin)

Question 18

What does sertraline inhibit at high doses?

Answer 18

Partial inhibition of CYP2D6 at high doses 150mg

Question 19

What is citalopram metabolised by? What should be done on discontinuation?

Answer 19

Citalopram metabolised by CYP2C19. gradually decrease dose on discontinuation

Question 20

What is mechanism of venlafaxine?

Answer 20

More potent inhibition of serotonin reuptake than norepinephrine reuptake. Noradrenaline implicated in regulation of emotions and cognition

Question 21

What is target of venlafaxine?

Answer 21

Serotonin transporter, noradrenaline transporter

Question 22

What are side effects of venlafaxine?

Answer 22

GI effects (nausea, diarrhoea), sexual dysfunction, anxiety, insomnia, hypertension (at high doses due to noradrenaline )

Question 23

What should be done on discontinuation of venlafaxine?

Answer 23

Gradually decrease on discontinuation

Question 24

What is mechanism of mirtazapine?

Answer 24

Antagonises central pre-synaptic alpha-2-adrenergic receptors, causing increased release of serotonin and norepinephrine. Antagonises 5HT2 receptor leaving 5HT1 receptor unopposed causing anti-depressant effects

Question 25

What is target of mirtazapine?

Answer 25

Alpha-2 adrenergic receptor, 5HT2 receptor

Question 26

What are side effects of mirtazapine?

Answer 26

Weight gain, sedation, low probability of sexual dysfunction, may exacerbate REM sleep behaviour disorder