Exam 3 Histamine/5-HT

Question 1

Histamine is a mediator of

Answer 1

Allergic and inflammatory response.

Question 2

Histamine stimulates

Answer 2

Pain and itching, decreased BP (vasodilation) increased HR (reflex)

Question 3

Where can histamine be found

Answer 3

Vesicles (mast cells). Other sources are brain and stomach.

Question 4

Distribution of H1 histamine subtype

Answer 4

Smooth muscle, endothelium, brain.

Question 5

Distribution of H2 histamine receptor subtype

Answer 5

Gastric mucosa, cardiac muscle, mast cells, brain.

Question 6

Describe the triple effect of Wheal and Flare

Answer 6

Leaky capillary endothelium, microcirculation smooth muscle (dilation increased fluid), sensory nerve endings (PG/Leukotrienes)

Question 7

Histamine effects on stomach

Answer 7

Histamine stimulates HCl

Question 8

Histamine effect on lungs

Answer 8

Bronchoconstriction

Question 9

First generation histamine antagonists

Answer 9

Benadryl, Dramamine, Phenergan, Atarax.

Question 10

Effects of first generation histamine antagonists

Answer 10

Sedative effects, ANS blocking

Question 11

Why are first generation histamine antagonists able to cause sedative effect

Answer 11

They cross BBB

Question 12

2nd generation Histamine antagonists

Answer 12

Allegra, Claritin, Zyrtec

Question 13

H1 antagonist used for

Answer 13

Sedation: Resemble antimuscarinic drugs, sleep aids.
Antinausea/antiemetic: motion sickness. Off label use for morning sickness.

Question 14

H2 antagonists uses

Answer 14

Acid blocker.

Question 15

H2 antagonist drugs

Answer 15

Famotidine, ranitidine (Zantac), cimetidine (Tagamet).

Question 16

5-HT 1A agonist

Answer 16

Buspirone.

Question 17

Buspirone is used for

Answer 17

Non benzo anxiolytic for GAD/OCD

Question 18

Serotonin Agonist targets

Answer 18

5-HT 1A
5-HT 1B
5-HT 1D
All are in the brain

Question 19

Serotonin antagonist targets

Answer 19

5-HT 2A
5-HT 3

Question 20

5-HT 1D/B agonist

Answer 20

Sumatriptan

Question 21

Sumatriptan is used for

Answer 21

Migraine HA

Question 22

Possible Cause of migraines

Answer 22

Increased CGRP binding and increased activation trigeminal nerve

Question 23

Migraine treatments

Answer 23

Pain relief: NSAID, ASA, NSAID + caffeine, Opioids.
Triptans- 5-HT 1D/B
Ergotamine- less effective, hardly used
Anti nausea- chlorpromazine, zofran.
Glucocorticoids- prednisone. Prophylactic

Question 24

How do triptans treat migraines

Answer 24

Bind to 5-HT 1D/B in cranial blood vessels. Preventing dilation and stretching of pain endings.

Question 25

Migraine preventative therapy

Answer 25

Beta blockers, CCBs, ACEi.
Antidepressants- SSRI/TCA
Anti seizure- valproate/topiramate
Botox- in skeletal muscle of temple, reducing tension HA.
Mabs- aimovig. 1/mo, $6000/year.

Question 26

Serotonin syndrome

Answer 26

Hyperthermia related to SSRI/MAOI/2nd gen antidepressants, sumatriptan, St Johns Wort.

Question 27

Treatment serotonin syndrome

Answer 27

Sedation with benzo, mechanical ventilation, paralysis.
Consider 5-HT2 block with cyproheptadine or chlorpromazine.

Question 28

Neuroleptic malignant syndrome precipitating drugs

Answer 28

D2 blocking antipsychotics

Question 29

Neuroleptic malignant syndrome tx

Answer 29

IV Benadryl, cooling if temp very high. Sedation with benzo.

Question 30

Serotonin antagonists act on 5-HT2

Answer 30

Phenoxybenzamine, cyrpoheptadine

Question 31

Serotonin 5-HT3

Answer 31

Ondansetron.

Question 32

List antidepressant drug classes in order from least side effects to most side effect

Answer 32

SSRI, SNRI, TCA, MAOI

Question 33

List SSRI drugs

Answer 33

Fluoxetine (Prozac), citalopram (Celexa), paroxetine (Paxil), sertraline (Zoloft), escitalopram (Lexapro)

Question 34

List SNRI drugs

Answer 34

Desvenlafaxine (Pristique)
Duloxetine (Cymbalta)

Question 35

List TCA drugs

Answer 35

Amitriptyline (Elavil)

Question 36

List MAOI drugs

Answer 36

Phenelzine (Nardil).
Newer/safer less efficacious Selegiline