L3- Antidepressants (SARIs, SNRIs, SSRIs)

Question 1

list the SSRIs

Answer 1

(selective serotonin reuptake inhibitors)
citalopram
escitalopram
fluoxetine
fluvoxamine
paroxetine
sertraline

Question 2

SSRI MOA

Answer 2

blocks SERT to inc 5-HT in synaptic cleft

Question 3

list some of the AEs of SSRIs (due to inc serotonergic activity)

Answer 3

nausea, GI upset, diarrhea (gut)

diminished sexual function and interest (spinal cord)

weight gain (not as common as above AEs)

Question 4

describe the dangerous drug interactions of SSRIs in general

Answer 4

serotonin syndrome if combined with MAOI or another serotonergic drug

Question 5

describe the drug interactions of SSRIs by specific drugs

Answer 5

Fluoxetine, Paroxetine: CYP2D6 inhibitor –> high potential for drug interactions

Fluvoamine: CYP1A2, CYP2C19, CYP3A4 –> high potential

Citalopram, Escitalopram, Sertraline –> low potential

Question 6

describe the result of SSRI overdose

Answer 6

seizures- low potential for fatality

Question 7

list the SARIs

Answer 7

(5-HT2 antagonist / reuptake inhibitors)

• nefazodone
• trazodone

Question 8

SARI MOA

Answer 8

• inhibits SERT / reuptake –> inc synaptic [5-HT] [weak activity]
• blocks 5-HT2 receptor –> to prevent stimulation and the anxiety and sexual dysfunction AEs [potent activity]

=> stimulation of 5-HT1A receptors (+ all other 5-HTRs)

Question 9

nefazodone uses

Answer 9

• not really prescribed

- causes hepatotoxicity

Question 10

trazodone:

• (1) additional mechanisms
• (2) are the main effects

Answer 10

1- α1 and H1 antagonist

2- sedation, hypnotic

Question 11

trazodone:

• (1) main use
• (2) rare AE

Answer 11

1- hypnotic

2- priapism

Question 12

list the SNRIs

Answer 12

(serotonin and NE reuptake inhibitors)

• venalfaxine
• duloxetine

Question 13

SNRIs:

• (1) is main MOA
• importantly lacks (2) activity, to differentiate it from TCAs

Answer 13

1- blocks SERT, NET

2- α1, H1, mACh receptor blockade

Question 14

discuss the difference in activities of venalfaxine and duloxetine

Answer 14

Duloxetine: inhibits SERT, NET at all doses

Venalfaxine:

• low doses, inhibits SERT&raquo_space; NET (more potent for SERT)
• high doses, inhibits SERT and NET
• weak inhibition of Dopa reuptake

Question 15

what is the key difference in terms of AEs with SNRIs vs SSRIs

Answer 15

much fewer CYP450 interactions