PNS and CNS drugs

Question 1

Drug class and indications of

Escitalopram

Answer 1

SSRI

Major Depression

General Anxiety Disorder

Question 2

SSRI P450 inhibitors

Drug interactions

Dosing instructions

Answer 2

Fluvoxamine

Fluoxetine

Paroxetine

Drug interactions: TCAs and Lithium

Decrease dose in patients with liver problems

Question 3

SSRI with active metabolite

Answer 3

Fluoxetine

Question 4

Drug interactions of SSRIs

Answer 4

1. Tramadol = increased seizure risk
2. NSAIDS = decrease SSRI function
3. Warfarin = displaced from plasma proteins
4. MAOIs = Serotonin syndrome
5. TCAs and Lithium with Paroxetine/Fluvoxamine/Fluoxetine = inhibit P450, increasing levels of TCAs and Lithium

Question 5

SSRI and Tramadol

Answer 5

Seizure

Question 6

SSRI and NSAIDs

Answer 6

Decreased SSRI action

Question 7

SSRI and warfarin

Answer 7

Decreased W binding to plasma cells and increased action

SSRIs are highly Protein binding!!

Question 8

SSRIs and MAOIs

Time to wait before switching drug type

Answer 8

Serotonin Syndrome

Start SSRIs 14 days post-MOAIs

Start MAOIs 7 days post-SSRIs

Question 9

Paroxetine/Fluvoxamine/Fluoxetine and Lithium or TCAs

Answer 9

Inhibit P450, decreasing metabolism and increasing action

Question 10

SSRI with risk of Torsadede pointes

Answer 10

Citalopram

Increased QT interval

Ventricular tachycardia

Question 11

Fluoxamine and Sumatriptan

Answer 11

Fluoxmine is SSRI

weakness, hyperreflexia, incoordination

Question 12

Side effects of Fluoxetine

Answer 12

Sexual dysfunction

Weight gain (different from other SSRIs)

Bleeding disorders

extrapyramidal signs

Question 13

SNRI with active metabolite

Answer 13

Venlafaxine

Question 14

SNRI that inhibits P450

Answer 14

Duloxetine

Question 15

Duloxetine and Thioridazine

Answer 15

Increased risk of ventricular dysrhythmias (Duloxetine has greater effect on NE than venlafaxine)

Question 16

Contraindications for SNRIs

Answer 16

Uncontrolled narrow-angle glaucoma (produces mydriasis)

Duloxetine = alcoholics (decreases P450 activity)

Question 17

Tertiary Amine Tricyclics

and MOA

Answer 17

CIA:

Clomipramine

Imipramine

Amitriptyline

Preferentially affect SERT

Question 18

Metabolism of TCAs

Answer 18

P450 in Liver

Conjugated to Glucuronic acid and excreted from kidneys

Question 19

TCAs and sympathomimetics

Answer 19

Potentiate response to direct-acting mimetics (block reuptake)

Decrease response to indirect-acting that promote release of transmitters b/c their uptake is also blocked

Question 20

Therapeutic index of TCAs

Answer 20

Very narrow!!

Question 21

TCAs and anticholinergic agents

Answer 21

Paralytic ileus

Hyperthermia

TCAs also bind ACh receptors

Question 22

TCAs and CNS depressants

Answer 22

synergistic

Question 23

TCAs and Tramadol

Answer 23

Increased seizure risk

block Na channels, incresing risk of seizure, here synergistic

Question 24

Treatment of TCA overdose

Symptoms

Answer 24

Physostimine

Symptoms:

1. anti-Muscarinic effects
2. Seizures
3. Cardiac Arrhythmia