Anti depressants

Question 1

Tricyclics we need to know

Answer 1

Imipramine and Desipramine

Question 2

Mechanism of Desipramine

Answer 2

Inhibit Reuptake of NE

Question 3

Mechanism of Imipramine

Answer 3

Inhibits reuptake of NE and seratonin

Question 4

Actions/Interations of tricyclics

Answer 4

No mood elevating effect in normal subjects
Elevates mood in depressed subjects after 2-3 weeks
Potentiates depressants – alcohol, opioids, anxiolytic-sedative-hypnotics
Slows gastric emptying – decreases effectiveness of Levadopa in Parkinson

Question 5

Adverse effects of tricyclics

Answer 5

Antimuscarinic effects: dry mouth, blurred vision, constipation, urine retention, sleepiness & light-headedness

Orthostatic Hypotension, weight gain, tachycardia

Low Therapeutic Index

Question 6

MAOI we need to know

Answer 6

Phenelzine

Question 7

Mechanism of Phenelzine

Answer 7

Irreversibly inhibits MAO A and B.

Causes increase of monoamines in synapse

Question 8

Actions/interactions of Phenelzine

Answer 8

Clinical improvement in about 3 weeks

Potentiates sympathomimetic amines – especially Tyramine (metabolized by liver) – Tyramine can’t be broken down by MAO

Question 9

Adverse effects of Phenelzine

Answer 9

Low Therapeutic Index
Tyramine + MAO inhibitor = massive adrenergic stimulation, HTN crisis
Pt needs to avoid foods w/tyramine
Also, need to wait at lease 14 days before starting SSRI and vice versa after discontinuing an MAOI

Question 10

Define Serotonin syndrome

Answer 10

Overactivation of 5HT-2A receptors leading to hyperthermia, muscle rigidity tremors, autonomic instability and confusion
Can be caused by MAOI and SSRI combined or MDMA
Treat with non-selective serotonin antagonist (cyproheptadine)

Question 11

SSRI’s we need to know

Answer 11

Fluoxetine, Sertraline and Escitalopram

Question 12

Mechanism of SSRI’s

Answer 12

Inhibit 5HT reuptake
Causes increase in 5HT levels and therapeutic effect thought to be achieved through 5HT-2A receptors but actions of receptors are much more complex than other NTs

Question 13

Define Autoreceptors

Answer 13

A receptor that can be stimulated by the same NT released from the presynaptic neuron on the presynaptic neuron causing the inhibition of more release of the NT

Question 14

Define Heteroreceptors

Answer 14

A receptor that can be stimulated by a NT, released from a presynaptic neuron, on a different presynaptic neuron causing the inhibition of release of a different NT

Question 15

Adverse effects of SSRI’s

Answer 15

Nausea, diarrhea, weight loss, anxiety, nervousness, insomnia (NOT SEDATIVES), sexual dysfxn, increased risk of suicidal thoughts

*Don’t use in Bipolar, can cause MANIA

Question 16

SNRI’s we need to know

Answer 16

Venlafaxine (Effexor/XR)

Question 17

Mechanism of Venlafaxine (Effexor)

Answer 17

Blocks 5HT and NE reuptake

Question 18

Raising dose venlafaxine

Answer 18

generally improves efficacy
Low dose = blocks 5HT reuptake
Med dose = blocks NE reuptake
High dose = blocks dopamine reuptake

Question 19

Adverse effects of venlafaxine

Answer 19

Doesn’t affect adrenergic, histamine, or cholinergic receptors – so it has less side effects than tricyclics.
However, still contraindicated with MAOI’s and vice versa

Question 20

Atypical antidepressant we need to know

Answer 20

Mirtazapine

Question 21

Mechanism of mirtazapine

Answer 21

Blocks presynaptic alpha2 receptors (autoreceptors on adrenergic and heteroreceptors on serotonergic…inhibits the inhibitory release signal from alpha2 receptors)
Causes increased levels of NE and 5HT

Question 22

Treatments for Bipolar we need to know

Answer 22

Lithium carbonate, Valpric Acid and carbamazepine