Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

2ND YEAR SYSTEMS: GI > Clinical pharmacology - Alimentary > Flashcards

Clinical pharmacology - Alimentary Flashcards

1
Q

What things do drugs target for alimentary disease

A

Acid suppression

GI motility

Constipation

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

Which drugs act to suppress excess acid in GI system

A

Antacids
H2-receptor antagonists
Proton pump inhibitors

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

What types of drugs affect GI motility

A

Anti-emetics - work against vomiting and nausea

Anti-muscarinics/other anti-spasmodics

Anti-motility

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

Which drugs are used for inflammatory bowel disease

A

Aminosalicylates

Corticosteroids

Immunosuppressants

Biologics

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

which drugs affect intestinal secretions

A

Bile acid sequestrants and ursodeoxycholic acid

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

How does histamine contribute to acid production?

A

acts on parietal cells which then secrete hydrochloric acid and intrinsic factor

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

How does Gastrin contribute to acid production?

A

stimulates proton pump which in turn triggers release of gastric acid

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

How do antacids work? when are they taken?

Give an example

A

they contain magnesium or aluminium which work to neutralise gastric acid

take when symptoms occur

Maalox

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do alginates like Gaviscon work to reduce effects of stomach acid?

A

form a viscous gel that floats on stomach contents and reduces reflux

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do H2 receptor antagonists reduce stomach acid? how are they taken? Reasons why a patient might take these?

A

Block histamine receptor thereby reducing acid secretion

orally or intravenously

Indicated in GORD/Peptic ulcer disease

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

Proton pump inhibitors:-

  • How do they work to reduce acid?
  • How are they administered?
  • Give an example of a commonly used PPI.
A

Block proton pump and thereby reduce acid secretion

Give in GORD/peptic ulcer disease - orally or IV

Omeprazole

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

Complications with proton pump inhibitors

A

Problems with GI upset and predisposition to c. difficile infection, hypomagnesaemia, B12 deficiency

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

How do PPIs result in vitamin B12 deficiencyt

A

since gastric acidity is required for vitamin B12absorption, acid suppression may lead to malabsorption and ultimatelydeficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What do prokinetics do ?

A

Prokinetic agents increase gut motility and gastric emptying

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

Give 2 examples of diseases that may need treated with prokinetics

A

gastroparesis - abnormal gastric emptying

GORD

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

Give 2 examples of some anti-emetic drugs

A

Metoclopramide - increases the movements or contractions of the stomach and intestines. Also increases the tone of the lower esophageal sphincter - GORD

Domperidone - probably acts by blocking dopamine receptors which inhibit post-synaptic cholinergic neurones

Both act on parasympathetic NS and alter control of smooth muscle and sphincter tone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where is the vomiting centre in the brain?

A

in the medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which drugs target the vomiting centre?

A

Anti-muscarinics & Anti-histamines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Motion sickness affects what part of the brainstem? and which drug targets this?

A

pons and medulla

anti-histamines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Sickness in response to drugs, toxins affects a place in the medulla called ____ ?

A

Chemoreceptor Trigger Zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which drugs are used to help drug/toxin induced vomiting

A

Dopamine antagonists

5 HT3,antagonists

Cannabinoids

22
Q

Vomiting caused by radiotherapy, Gastroenteritis or some drugs is detected where?

A

in the pharynx and GIT which then goes to the vomiting centre in the medulla

23
Q

Give 1 pro and con for anti-motility drugs?

A

Can prevent diarrhoea

but can also cause constipation

24
Q

How do drugs that decrease motility work?

A

work via opiate receptors in GI tract to decrease ACh release

this in turn decreases smooth muscle contraction and increases anal sphincter tone so chyme moves slower down GI tract

25
Q

Why does Loperamide (Immodium) not have many central opiate effects?

A

it isn’t well absorbed across the blood brain barrier so it doesn’t access the CNS

26
Q

What are anti-spasmoidic used for?

A

to reduce symptoms due to IBS, renal colic

27
Q

How do anti-spasmoidic work?

A

Anti-cholinergic muscarinic antagonists - inhibit smooth muscle constriction in the gut wall, producing muscle relaxation and reduction spasm.

Direct smooth muscle relaxants

Calcium-channel blockers - reduce calcium required for smooth muscle contraction

28
Q

What are the 4 types of laxative? Give examples

A

Bulk (e.g. Isphagula)

Osmotic (e.g.
Lactulose)

Stimulant (e.g. Senna)

Softeners (e.g. Arachis oil)

they either work by increasing bulk or drawing fluid into the gut

29
Q

Issues with laxatives?

A

Obstruction

Route of administration (Oral or Rectal)

Need for other measures - Osmotic laxatives will not work without adequate fluid intake

Misuse (weight loss)

30
Q

Which drugs are used for IBD?

A

Aminosalicylates - anti -inflammatory

Corticosteroids

Immunosuppressants (Azathioprine)

31
Q

Corticosteroids: effects? administration? contraindications?

A

Anti-inflammatory effects

Given orally, IV or rectally

Usual concerns and contraindications:-
Osteoporosis

Cushingoid features (excess cortisol) including weight gain, DM, HT

Increased susceptibility to infection

Addisonian crisis with abrupt withdrawal

32
Q

Immunosuppressants for IBD:-

How do they work?

A

Prevents the formation of purines required for DNA synthesis so reduces immune cell proliferation

Adverse effects mainly relate to bone marrow suppression but also azathioprine hypersensitivity and organ damage (lung, liver, pancreatitis)

Numerous drug interactions

Specialist use and close monitoring required

33
Q

What sorts of things does the drug Infliximab treat? (3)

A

Current TB or other serious infection

Multiple sclerosis

Pregnancy/breast feeding

34
Q

Adverse affects of infliximab? (type of biologic - treats a number of autoimmune diseases)

A

Risk of infection, particularly TB so all patients should be screened

Infusion reaction (fever, itch)

Anaemia, thrombocytopenia, neutropenia

?Demyelination - nerve deterioration

Malignancy

35
Q

Types of biologics other than infliximab

A

Certolizumab

Adalimumab

Natalizumab

Golimumab

Vedolizumab

36
Q

Which drugs affect biliary secretion? (2)

A

Cholestyramine

Ursodeoxycholic Acid

37
Q

How does Cholestyramine work?

A

Reduces bile salts by binding with them in the gut and then excreting as insoluble complex
May affect absorption of other drugs so should be taken separately

May affect fat soluble vitamin absorption so may decrease vitamin K levels (affecting clotting and warfarin)

38
Q

How does Ursodeoxycholic Acid

affect biliary secretion?

A

Used to treat Gallstones and Primary Biliary Cirrhosis (PBC)

Inhibits an enzyme involved in the formation of cholesterol, altering amount in bile and slowly dissolving non-calcified stones

39
Q

What can GI or liver disease affect in regards to drug processing?

A

Absorption (more so rate of absorption rather than total absorption)
Distribution
Metabolism
Excretion

40
Q

What does drug absorption in the gut depend on?

A

pH

Gut length

Transit time
e.g. Digoxin, Warfarin

41
Q

How can low albumin levels reduce drug distribution

A

drugs that are usually bound to protein are then free

free drug conc increases and decreased binding overall

42
Q

What problems can there be with drug metabolism?

A

Increased gut bacteria (metabolise drugs so increased dose needed)

Gut wall metabolism (disease may reduce first pass metabolism)
e.g. Morphine

Liver blood flow (drugs with a high extraction ratio - the organ is capable of removing all the drug presented to it, independently of plasma binding)

liver enzymes - toxicity

(has to be severe liver disease to be problematic)

43
Q

GI adverse effects (

A

GI bleeding/ulceration

changes to gut bacteria

44
Q

what are the most common drugs to cause GI bleeding or ulceration?

A

low dose aspirin/NSAIDs or warfarin

45
Q

Give examples of some changes that can occur with gut bacteria?

A

Loss of Oral Contraceptive activity

Reduced vitamin K absorption (increased prothrombin time)

Overgrowth of pathogenic bacteria (e.g. Clostridium difficile)

46
Q

Liver injury due to GI drug therapy

A

Intrinsic hepatotoxicity (predictable, dose–dependent, acute) type A ADR

Idiosyncratic hepatotoxicity (unpredictable, not dose dependent, and may occur at any time – may be part of a hypersensitivity reaction) type B ADR

May be due to the drug itself or an active metabolite

Generally hepatitis or cholestasis, but can mimic any pattern of acute or chronic liver disease

47
Q

Risk factors for hepatotoxictiy? (5)

A 
Age (elderly at risk)
Sex (female at risk)
Alcohol consumption
Genetic factors
Malnourishment
48
Q

Classification tool for hepatotoxicity

A

Child-Pugh classification

The individual scores are summed and then grouped as:
<7 = A
7-9 = B
>9 = C

Takes into consideration things like bilirubin, albumin levels, PT, ascites adn encephalopathy

49
Q

2 drugs that are hepatotoxic

A

methotrexate

azathioprine

50
Q

Opiates may precipitate what by increasing sedation?

A

encephalopathy

2ND YEAR SYSTEMS: GI (38 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions