E2. Autacoids Flashcards

1
Q

What are the 4 groups that are classified as autacoids?

A
  • Histamine
  • Serotonin (5‐HT)
  • Prostaglandins (PGs)
  • Peptides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q
Select the drugs that are  serotonin (5 –HT) agonists?(can be more than one)
A. Fluoxetine
B. Ranitidine
C. Ondansetron
D. Cisapride
E. Metoclopramide
A

D. Cisapride
A. Fluoxetine
C and E are antagonists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does Cisapride act on (MOA), and what is its use?

A

– Mechanism of action
• 5‐HT4 receptor agonist in enteric neurons
– Use
• Prokinetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does Fluoxetine work?

A

Acts by increasing serotonin levels in the brain. Increasing those levels improves signs of depression in humans.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the clinical use for Fluoxetine?

A

-Approved for treatment of canine separation anxiety in conjunction with a behavior modification plan
• Used in dogs and cats to treat other behavioral disorders such as
aggression, obsessive compulsive behaviors and anxiety
• Used in treatment of cats with inappropriate elimination and urine marking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are some side effects you will see from Fluoxetine use? (5)

A

Nausea, anorexia, anxiety, irritability, and sleeping disturbances. (More information look at page 267)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What drugs are serotonin (5 – HT) antagonist? (3)

A

Cyproheptadine, Onidasetron, Metroclopramide.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the mechanism of action for Cyproheptadine?(3)

A
  • Blocks H1‐receptors
  • Blocks serotonin receptors
  • Inhibition of serotonin inhibits ACTH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the three uses for Cyproheptadine?

A
  • Antihistamine
  • To stimulate appetite in small animals
  • In the treatment of “serotonin syndrome” in dogs and cats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the mechanism of action for Onidasetron and Metroclopramide?

A

Onidasetron:
• 5‐HT3 receptor antagonist (central and peripheral)

Metroclopramide:
• 5‐HT3 receptor antagonist
• D1 and D2 receptor antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the clinical uses for Onidasetron and Metroclopramide?

A

Onidasetron:
• Prevention and treatment of anticancer chemotherapy‐ induced nausea and vomiting

Metroclopramide:
• Antiemetic
• Prokinetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Look at the slides 1-3/6 for histamine information

A

.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the four drugs/groups that generally inhibit histamine release? (4/6)

A

– catecholamines (epinephrine)
– cromolyn sodium
– phosphodiesterases (aminophylline)
– glucocorticoids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
When you inhibit H1 receptors you are blocking which of the following?
A. Inflammation
B. Anaphylaxis
C. Allergies
D. Drug reactions
E. All of the above
A

E. All of the above

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the H2 receptors required for?

A

Gastric acid secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the major H1 mediated effects? (4) (slide6-7/6)

A
  • Contraction of smooth muscles (esp. GI, bronchioles, uterus and large vessels classically resulting in bronchoconstriction).
  • Vasodilation and then contraction of small vessels – capillaries, arterioles and venules - which leads to increased permeability (shock, hypotension, edema).
  • Positive inotropic effect.
  • Other effects such as CNS stimulation/alterations in sleep/wake cycles, itching, vomiting and
    inappetence, and local reflex vasodilation.
17
Q

What is the major H2 mediated effect?

A

Gastric acid secretion

18
Q

Look at slides 9 – 10/6. More important just to know that they are H3 and H4 receptors

19
Q

What drugs are your H1 agonists (first generation)? (10)

A

Pyrilamine(Equiphed®)
Diphenydramine(Benadryl®),
Dimenhydrinate (Dramamine, Gravol®),
Chlorpheniramine(Chlor-trimetron®)

20
Q

Of the 10 first-generation H1 blockers how many are primarily used for something else?

21
Q
Which of these drugs are used as appetite  stimulants in cats?
A. Dimenhydrinate (Dramamine, Gravol®)
B. Cyproheptadine(Periactin®)
C. Meclizine(Antivert®)
D. Any of the above can work
E. None of the above work
A

B. Cyproheptadine(Periactin®)

22
Q
Which of these drugs are used to treat vestibular nausea?
A. Dimenhydrinate (Dramamine, Gravol®)
B. Cyproheptadine(Periactin®)
C. Meclizine(Antivert®)
D. Any of the above can work
E. None of the above work
A

A. Dimenhydrinate (Dramamine, Gravol®)

23
Q
Which of these drugs are used to treat for "old dog" vestibular disease in canines?
A. Dimenhydrinate (Dramamine, Gravol®)
B. Cyproheptadine(Periactin®)
C. Meclizine(Antivert®)
D. Any of the above can work
E. None of the above work
A

C. Meclizine(Antivert®)

24
Q

What are the three drugs that are second-generation H1 blockers?

A
  • Terfenadine (Seldane®)
  • Loratadine (Claritin®)
  • Fexofenadine (Allegra®)
    
25
True or false: H1 antagonists have a wide distribution (including the CNS (first and second generation)) and are poorly absorbed orally.
False. Are readily absorbed orally and only the first generation goes to the CNS.
26
Which generation of H1 antagonists has the longer duration of action?
``` Second generation (12 to 24 hours) *first generation 3 to 12 hours. ```
27
How are the H1 antagonists metabolized, and in what are they excreted in?
Metabolized by the liver, and excreted in the urine.
28
What are the therapeutic uses for H1 antagonist? (4) (slide 16/6)
– Allergy – Anaphylaxis – Anti-motion sickness – Mild sedative
29
Look at slide 17/6 for side effects of H1 antagonist
.
30
What are the 4 H2 drugs?
– cimetidine – ranitidine – famotidine – nizatidine
31
How can you tell the difference between your H2 blockers and your H1 blockers?
All the H2 blockers end in "tidine"
32
What type of antagonists are the H2 receptor antagonist?
Competitive antagonists
33
``` Which of the following drugs has immunomodulating activity? A. Famotidine B. Nizatidine C. Cimetidine D. Ranitidine ```
``` C. Cimetidine *Hepaticmicrosomalenzymeinhibitor(numerousdrug-druginteractions). Used to reduce gastric acid and also in treatment of equine melanoma (because of immunomodulating activity (alteration of T-cell function and cell-mediated immunity). ```
34
``` What drug should you use if you want to control gastric acid only? A. Famotidine B. Nizatidine C. Cimetidine D. Ranitidine ```
A. Famotidine
35
``` What drug can be used for gastric acid and also for the G.I. prokinetic activity? A. Famotidine B. Nizatidine C. Cimetidine D. Ranitidine ```
B. Nizatidine | D. Ranitidine
36
What system is responsible for metabolizing Cimetidine, ranitidine and famotidine?
Cytochrome p450 system
37
True or false: | H2 blockers have good oral bioavailability, and are less lipid soluble so they don't cross the blood brain barrier.
True
38
What is an issue with cimetidine involving the cytochrome p450 system and other drugs that use that system for metabolization?
Cimetidine will inhibit that system reducing the clearance of other drugs.