2. Drug treatment for depression

Question 1

Types of commonly used drugs for the treatment of depression

Answer 1

1. Selective Serotonin Re-uptake Inhibitors (SSRIs)
2. TriCyclic antidepressants (TCAs)
3. Serotonin Norepinephrine Re-uptake Inhibitors (SNRIs)
4. NorAdrenergic & Specific Serotonergic Antidepressants (NaSSAs)

Question 2

MOA of Selective Serotonin Re-uptake Inhibitors (SSRIs)

Answer 2

Inhibition of serotonin reuptake in synaptic cleft → ↑ serotonin levels

Question 3

Examples of Selective Serotonin Re-uptake Inhibitors (SSRIs)

Answer 3

1. Fluoxetine
2. Escitalopram
3. Sertraline
4. Paroxetine

Question 4

Adverse effects of Selective Serotonin Re-uptake Inhibitors (SSRIs)

Answer 4

1. Anxiety
2. Weight loss/gain
3. Headache, nausea
4. Sexual dysfunction
5. Hyponatremia
6. No fatality in overdose

Question 5

Drug-drug interactions of Selective Serotonin Re-uptake Inhibitors (SSRIs)

Answer 5

1. SSRIs inhibit various P450 enzymes:
   Fluoxetine > paroxetine > sertraline > escitalopram
2. Do not take SSRIs with MAOI, or St John’s wort
   Risk of Serotonin syndrome: confusion, agitation, restlessness, stomach or intestinal symptoms, a sudden high body temperature, an extremely high bp, or severe seizures.

Question 6

MOA of TriCyclic antidepressants (TCAs)

Answer 6

Inhibition of serotonin and norepinephrine reuptake in synaptic cleft → ↑ serotonin and norepinephrine levels

Question 7

Examples of TriCyclic antidepressants (TCAs)

Answer 7

1. Amitriptyline

2. Imipramine

Question 8

Adverse effects of TriCyclic antidepressants (TCAs)

Answer 8

1. CNS effects: sedation, fatigue
2. Cardiac rhythm: tachycardia, arrhythmias
3. Postural hypotension
4. Anticholinergic effects: dry mouth, constipation, glaucoma, blurred vision, urinary retention, constipation
5. Fatality in overdose

Question 9

MOA of Serotonin Norepinephrine Re-uptake Inhibitors (SNRIs)

Answer 9

Inhibition of serotonin and norepinephrine reuptake in synaptic cleft → ↑ serotonin and norepinephrine levels

Question 10

Example of Serotonin Norepinephrine Re-uptake Inhibitors (SNRIs)

Answer 10

Venlafaxine (act like TCAs)

Question 11

Adverse effects of Serotonin Norepinephrine Re-uptake Inhibitors (SNRIs)

Answer 11

1. CNS effects: Agitation, irritable or drowsy
2. CVS effects: BP may be affected at higher dose
3. Hyponatremia

Question 12

MOA of NorAdrenergic & Specific Serotonergic Antidepressants (NaSSAs)

Answer 12

Act by antagonizing the α2-adrenergic receptor and certain serotonin receptors such as 5-HT2A and 5-HT2C, but also 5-HT3, 5-HT6, and/or 5-HT7 in some cases

Question 13

Example of NaSSA

Answer 13

Mirtazapine