Brainscape's Knowledge GenomeTM

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


See full index

ME2019 PART 2 > Drug Interactions > Flashcards

Drug Interactions Flashcards

1
Q

What is a drug interaction?

A

Modification of a drugs effect by prior or concomitant administration of another drug

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

What are different things involved in drug interactions?

A

Drugs

Herbal

Food

Drinks

Pharmacogenetics

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

What is the object drug?

A

Drug which is effected by these interactions

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

What is the precipitant?

A

Agent which precipitants such a reaction

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

What are examples of drug interactions which are not always decremental?

A

Hypertension

Parkinson’s

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

What is epidermiology?

A

Branch of medicine that deals with incidence, distribution and possible control of disease

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

What is the incidence of significant interactions?

A

Relatively low at 1%

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

What are some examples of drug involved in serious reactions?

A

Lithium

Warfarin

Erythromycin

Linezolid

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

What are drugs involved in serious interactions often?

A

Potent with a narrow therapeutic index, meaning a small change in blood levels induce toxicity

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

What do lots of foods interact with?

A

Warfarin

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

What happens to the probability of a drug-drug interaction with more medicaments?

A

Increases exponentially

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

Who are some people more likely to suffer from a drug-drug interaction?

A

Elderly

Young

Critically ill

Patients undergoing complicated surgery procedures

Patients on many medications

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

What kinds of conditions make people susceptable to drug interactions?

A

Chronic

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

What are examples of chronic conditions that make people more susceptable to drug interactions?

A

Liver disease

Renal impairment

Diabetes mellitus

Epilepsy

Asthma

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

Who usually experience severe interactions?

A

Patients with chronic conditions

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

What is pharmacodynamics?

A

Study of how a drug affects an organism

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

What is pharmacokinetics?

A

Study of how the organism affects the drug

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

What can drug interactions be?

A

Additive or synergistic

Antagonistic

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

What can interactions be due to?

A

Changes in drug transport

Fluid and elctrolyte disturbances

Indirect pharmacodynamics interactions

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

What are the 4 stages of pharmacodynamics?

A

Absorption

Distribution

Metabolism

Elimination

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

What can a drug do to the pharmacokinetics of another drug?

A

Alter it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Why is it possible to predict potential interactions?

A

Due to marked inter-individual variations in pharmacodynamics process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is it not possible to predict?

A

Patients who will have a clinically significant interaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What do absorption interactions mechanisms include?

A

Formation of insoluble complexes

Altered pH

Altered bacterial flora

Altered GIT motility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What do most absorption interactions lead to?

A

Change in absorption rate and not the extend of absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

When is delayed absorption likely to have a great impact?

A

When the drug has a short half life or when we want high plasma levels quickly

27
Q

How can absorption interactions be avoided?

A

2-4 hours are left between administration of drugs

28
Q

What do some drugs do in the GI tract?

A

Bind to each other

29
Q

What are examples of drugs that bind to each other in the GI tract?

A

Tetracycline and erythromycin complex with iron, calcium and magnesium

Cholestryamine resin used to bind cholesterol in the GI tract also binds to other drugs like warfarin

30
Q

What is absorption affected by (relates to acids/bases)?

A

Degree of ionisation which is dependant on pH

31
Q

Why do drugs increase pH?

A

Reducing the [H+] ions

32
Q

What are some drugs that increase pH?

A

H2 antagonists

Proton pump blockers

Antacids

33
Q

What destroys normal gut flora?

A

Broad spectrum antibiotics

34
Q

Where are most oral medicines absorbed?

A

Small intestine

35
Q

What is the rate limiting step of most oral medicines?

A

Gastric emptying

36
Q

What can some drugs do to gastric emptying?

A

Increase or decrease it and so impact absorption of other drugs

37
Q

What is the drug interaction in distribution?

A

Protein-protein displacement

38
Q

When does protein-protein displacement occur?

A

When there is a reduction in the extent of plasma protein binding of a drug caused by the presence of another drug

39
Q

What does displacement of a drug from a plasma protein cause?

A

Increased bioavailability of that drug

40
Q

What are the 2 most important plasma proteins?

A

Albumin

Alpha1-glycoprotein

41
Q

What protect patients from distribution interactions?

A

Increased metabolism and excretion

42
Q

What drugs cause distribution interactions?

A

Ones which are highly protein bound

43
Q

What are examples of drugs which are highly protein bound?

A

Indomethacin

Warfarin

Ibuprofen

44
Q

When do interactions involving metabolism occur?

A

When one drug induces or inhibits the metabolism of another

45
Q

Where does metabolism of drugs commonly occur?

A

In the liver via the cytochrome P450 system

46
Q

What are some drugs that can inhibit the cytochrome system?

A

Erythromycin

Cimetidine

47
Q

What do drugs inhibiting the cytochrome system cause?

A

Inhibition of metabolism of drugs that use that cytochrome

48
Q

What are drugs that can be affected by drugs inhibiting the cytochrome system?

A

Warfarin

Diazepam

49
Q

What are some drugs that are potent inducers of cytochrome P450?

A

Barbiturates

Carbamazepine

50
Q

How long does it take for the effects of enzyme induction to be seen?

A

2-3 weeks

51
Q

What factors impact the effect of enzyme induction been seen?

A

Age

Disease

Genetics

Concurrent drug therapy

52
Q

What are examples of drugs inducing the production of cytochrome P450 enzymes?

A

Rifampicin inducing CYP 3A4 increases metabolism of Ciclosporin

St John’s wort induces CYP 3A4 to increase metabolism of ciclosporin

53
Q

Where are most drugs excreted?

A

In urine or bile

54
Q

What do interactions in excretion involve changes in?

A

Glomerular filtration rate

Tubular secretion

55
Q

What is glomerular filtration rate?

A

How much blood passes through the glomeruli each minute

56
Q

What is the glomeruli?

A

Tiny filters in the kidney that filter waste from blood

57
Q

What is an example of a drug that inhibits excretion?

A

Calcium channel blockers

58
Q

When do pharmacodynamic interactions occur?

A

When the action of a drug is changed due to another drug acting directly on the same receptor or indirectly on a different receptor

59
Q

What can pharmacodynamic interactions be?

A

Direct

Indirect

Antagonistic

Synergistic/Agonistic

60
Q

What is an example of pharmacodynamic direct antagonsm?

A

Beta blockers blocking the site of agonists

61
Q

What is an example of pharmacodynamic synergistic interactions?

A

Two drugs with the same pharmacological effect acting on the same receptor are given concurrently

62
Q

What is an example of a pharmacokinetic indirect agonism?

A

CNS depression

Warfarin and NSAIDs

63
Q

What is an example of pharmacodynamic indirect antagonist?

A

NSAIDs and antihypertensive medication

NSAIDs and treatment for heart failure

64
Q

What is the process of clinically dealing with an interaction?

A

1) Determine if the interaction is clinically important
2) Will altering the dose timing solve the interaction
3) Will using an alternative solve the interaction
4) If no for all of above, adjust the dosage and monitor the drug level and physiological function

ME2019 PART 2 (45 decks)

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