Lecture 12- Over the counter drugs - Allergy and Insomnia

Question 1

____ are caused by the hypersensitivity of the immune system to typically harmless substances in the environment.

Answer 1

Allergies

Question 2

Symptoms of allergies include?

Answer 2

• red eyes
• itchy rash
• sneezing
• runny nose
• shortness of breath
• swelling

Question 3

The mechanism of allergies involve ____ ____ ____ (IgE). ____ cells react inappropriately to an allergen to produce IgE antibodies against the allergen. Antibodies bind to the receptors on mast cells or on ____phils. Subsequent exposure to the allergen triggers release of inflammatory chemicals such as ____.

Answer 3

Immunoglobin E antibodies; B cells; basophils; histamine.

Question 4

How many classes of histamine receptors are there?

Answer 4

4
* H1: allergic inflammation
* H2: gastric acid secretion
* H3: neurotransmission
* H4: immunomodulation

Question 5

Which H receptors play a predominant role in allergic response?

Answer 5

H1

Question 6

H____ receptors are located in smooth muscles, on vasuclar endothelial cells, in the heart, and in the nervous system.

Answer 6

H1

Question 7

Drugs that interfere with histamine signaling in the brain will have symptoms associated with disrupted ____ or ____.

Answer 7

wakefulness; drowsiness

Question 8

Histamine H1 receptors occur throughout the brain, with particularly high density in regions involved in ____ and ____ (thalamus, cortex and noradrenergic, serotonergic and dopaminergic nuclei)

Answer 8

arousal and waking

Question 9

Which neurotransmitter is important in the wake-promoting system?

Answer 9

histamine

Question 10

____ readily crosses the blood-brain barrier and inversely agonizes the H1 CNS receptors, resulting in ____; it also supresses activity in the ____.

Answer 10

drowsiness; nTS

Question 11

Drugs with high affinity will have ____ EC50.

Answer 11

low EC50 as the drug concentration required is less to occupy effectors.

Question 12

____ and ____ have similar affinities to the H1 receptor, so you need relatively high doses of ____ to block ____ effects.

Answer 12

Diphenhydramine; histamine

Question 13

What is an example of first generation antihistamines?

Answer 13

Diphenhydramine

Question 14

High effinity = ____ Ki

Answer 14

low

Question 15

What is Ki?

Answer 15

concentration needed to displace 50% of the ligand.

Question 16

pKi is the ____ ____ of Ki (like pH). A drug with a high affinity will have a ____ pKi (low ki)

Answer 16

negative log; high pKi

Question 17

First generation antihistamines bind with relatively high affinity to ____ ____ receptors which have anticholinergic effects. This can lead to side effects such as ____ ____, ____ and ____.

Answer 17

muscarinic cholinergic; dry mouth; constipation and confusion.

Question 18

____ develops rapidly to the sedative effects of diphenhydramine.

Answer 18

tolerance.

Question 19

Diphenhydramine also decreases the quality of sleep (____ time in REM and ____ time in light sleep)

Answer 19

less;more

Question 20

Which generation antihistamines have higher selectiviery for the H1 receptors?

Answer 20

Second generation.

Question 21

Second-generation anti-histamines have poor ____ ____ ____ permeability, so they lack the sedative effects.

Answer 21

Blood-brain barrier

Question 22

Which generation of anti-histamines have longer duration of action?

Answer 22

Second generation.

Question 23

____ is an H1 receptor antagonist in the second generation anti-histamines.

Answer 23

Cetirizine

Question 24

Which of the following drug, Diphenhydramine or cetirizine, have a longer duration of action?

Answer 24

cetirizine (24 hours) while diphenhydramine is 4-6hours.

Question 25

____ is an inverse agonist at the H1 receptor of the second generation anti-histamines.

Answer 25

Loratadine.

Question 26

Loratadine is mostly bound to ____ ____ (i.e, albumin). The ____ however are not active.

Answer 26

plasma proteins; protein

Question 27

When loratadine is given orally, rapid ____ ____ ____ converts loratadine into _____.

Answer 27

first pass metabolism; desloratidine, therefore loratadine is a prodrug.

Question 28

When loratadine is given orally, rapid ____ ____ ____ converts loratadine into _____.

Answer 28

first pass metabolism; desloratidine, therefore loratadine is a prodrug.

Question 29

Which of the following drug, loratadine or desloratadine, has a longer duration of action?

Answer 29

desloradatine.

Question 30

____ (1/2) generation OTC anti-histamine drugs have ____( high/low) selectivity for the H1 receptor (off-target side effects) and penerate the blood-brain barrier, so they are ____ (sedative/non-sedative).

Answer 30

1; low; sedative

Question 31

____ (1/2) generation OTC anti-histamine drugs have ____( high/low) selectivity for the H1 receptor (off-target side effects) and have poor penetration the blood-brain barrier, so they are ____ (sedative/non-sedative).

Answer 31

2; high; non-sedative.

Question 32

First generation antihistamines are marketed for ____, ____, ____, and ____ whereas second generation anti-histamines were devleoped to isolate and optimize the anti-allergy effects.

Answer 32

allergy, insomnia, cough and cold.