Adverse drug reactions Flashcards
1
Q
What does ADR stand for
A
Adverse drug reactions
2
Q
What can adverse drug reactions be classified as
A
- Overdosing
- Side effects
- Secondary effects
- Idiosyncratic reactions
- Teratogenic effects
- Allergic reaction
- DRUG INTERACTIONS
3
Q
The elderly are usually on how many drugs
A
frequently on 7+ drugs
4
Q
What can overdosing occur due to
A
- Sucidal intent
- Failure to calculate paediatric or elderly persons dose correctly
- Failure to alter dose in renal or hepatic impairment/ disease
5
Q
What do we define side effect as
A
An unwanted effect attributable to the known pharmacological action of the drug
6
Q
What do secondary effects occur as a result of
A
A consequence of prescribing the due but are not a direct pharmacological action of the drug
7
Q
What are idiosyncratic reactions
A
Genetic predisposition to a rare reaction to a medication
8
Q
What are teratogenic effects
A
When drugs given to pregnant women cause damage or death to the foetus
9
Q
What can the teratogenic effect of phenytoin be
A
Cleft lip, learning impairments
10
Q
What can the teratogenic effect of valproate be
A
Serious developmental disorders in uptown 40% of cases
Congenital disorders in 10% cases
11
Q
What can the teratogenic effect of MYCOPHENOLATE be
A
Congenital heart disease
Eye abnormalities
12
Q
What can the teratogenic effect of tetracycline be
A
Mottling of teeth and bones
13
Q
What are hypersensitivity reactions not dependent on
A
NOT DOSE dependent
13
Q
What are hypersensitivity reactions
A
Drug molecules when bound to plasma porins can act as happens and trigger immunological responses
13
Q
What are hypersensitivity reactions usually due to
A
Due to a metabolite rather than the drug itself
13
Q
How do we classify hypersensitivity reactions
A
Type I, II, III, IV
14
Q
What is a type I hypersensitivity reaction
A
Anaphylaxis
15
Q
What is a type II hypersensitivity reaction
A
Cytotoxic
16
Q
What is a type III hypersensitivity reaction
A
Antibody antigen complex
17
Q
What is a type IV hypersensitivity reaction
A
Cell mediated delayed
18
Q
What accounts to the most ADRs
A
Drug interactions account for uptown 20% of all ADRs
19
Q
What are drug interactions
A
Administration of drug A which modifies behaviour of drug B
20
Q
Name the 2 types of drug interactions
A
- Pharmacodynamics
2. Pharmacokinetic
21
Q
What is pharmacodynamic drug interaction
A
The effect occurs without the concentration of drug B changing in the tissue fluid
22
What is a pharmacokinetic drug interaction
The effect changes due to an alteration in the concentration of drug B at its target tissue/cell
23
Who are most likely to experience drug interaction
Patients on multiple drugs especially the elderly
23
To what can alcohol have a drug itneraction with and what type of drug interaction is it
Can interact with antihistamines, opioids and benzodiazepines causing increased somnolence
Pharmacodynamic drug interactions
23
What can aspirin interact with and what type of drug interaction is it
Warfarin or clopidogrel increasing risk of haemorrhage
Pharmacodynamic drug interactions
23
What can NSAIDs and antihypertenisce lead to and what type of drug interaction is this
Lead to paradoxical hypertension
Pharmacodynamic drug interactions
24
What is penicillin antagonised by
Tetracylcine
25
What does ADME stand FOR
Absorption
Distribution
Metabolism
Excretion
26
Give an example of drug interactions that interfere with absorption
Loocal anaesthetic and a vasoconstrictor - reduced blood flow to the tissue leads to prolonged effect of the anaesthetic agent giving a bloodless field
27
Give an example of a drug interaction that interfered with albumin
Main type is where 2 drugs compete for binding to albumin eg aspirin is 50% bound to albumin and warfarin is 99% bound so administering both radically increases the risk of life-threatening bleeds
28
Give an example of a drug interaction that interferes with metabolism
1. Enzyme inducers
| 2. Enzyme inhibitors
29
Give an example of a drug that acts as a enzyme inducer
Soem drugs increase P450 production eg carbamazepine, rifampicin, ethanol, phenobarbitone all induce enzymes
30
Give example of enzyme inhibiting drugs
1. Erythromycin
2. Metronidazole
3. Azole antifungal
31
What can erythromycin react with
1. Warfarin (increased risk bleeding)
2. Carbamazepine (ataxia)
3. Calcium channel blockers (hypotension)
4. Simvastatin (increase in muscle breakdown)
5. Clopidogrel (increased risk of bleeding)
32
What drugs can metronidazole affect
1. Ethanol (nausea, dizziness due to the antibiotic inhibiting alcohol’s metabolism)
2. Warfarin (increased risk bleeding)
3. Phenytoin (metronidazole raises the plasma concentration of phenytoin due to inhibited metabolism increasing risk of toxicity)
33
What drugs can Azole antifungal affect
Warfarin (increased risk bleeding)
34
Why might drugs interfere with excretion
May be due to one agent not being excreted by the kidney due to another agent blocking tubular secretion
35
What clinical manifestations of ADRs can be seen in and around the oral cavity
1. Infections
2. Lichenoid drug reactions
3. Lupus like drug reactions
4. Vesicullobullous drug reactions
5. Erythema multiform and Steven Johnsons syndrome
6. Other drug induced ulceration
7. Fixed drug reactions
8. Hyper/hypo-pigmentation
9. Ulticaria and angioedema
10. Gingival enlargement
11. Salivary gland involvement
12. Sensory abnormalities
13. Motor abnormalities
14. Abnormalities of mineralised tissues
36
Why can ADRs present as infection to oral cavity
Either beducase the normal immune response is suppressed or there is damage to the mucosal surfaces
37
What drugs can cause a fungal infection
Corticosteroids (topical, oral or inhaled)
| Broad spectrum antibiotics
38
Give an example of a fungal infection caused by ADR
Candidosis
39
Give examples of viral infections that can result due to ADRs
1. Herpetic stomatitis (HSV 1 or 2),
2, Oral Hairy Leukoplakia (EBV)
3. Kaposi’s sarcoma (HHV 8)
4 .Papillomata (HPV)
40
Give examples of drugs that can cause viral ADRs
Anti rejection drugs in past transplant patients
41
What is lichen planus (OLP)
The disease in the absence of an identifiable cause
42
Why might a lichenoid reaction occur
Due to exposure to a triggering agent (dental materials and various drugs included)
43
List soem common drugs implicated in lichenoid reactions
1. NSAIDs
2. ACE-inhibitors
3. Beta blockers
4. Thiazide diuretics
5. Carbamazepine
44
What can vesicullobullous drug reactions produce
Vesicles and bullae
45
What are erythema multoforne and Steven Johnsons syndrome involved with
Immune related ulcerations of the skin and mucosa
45
What can trigger erythema multiform and Steven johns syndrome
NSAIDs
Penicillins
Sulphonamides
Carbamepine
45
Give examples of other drug induced ulcerations
1. Chemical burn
2. Sloughing and ulceration
3. Ocular ulceration
46
What can cause chemical burs
Placing an aspirin next to a tooth which is hurting
47
What can cytotoxic agents cause
severe mucosal sloughing and ulceration - ‘oral mucositis’ is well known during this phase of cancer treatment
48
What is nicorandil a treatment for
Angina
49
What side effects can nicorandil cause
persistent oral, rectal and ocular ulceration
50
What are fixed drug reactions
Characteristic finding of a development of a rash at the same anatomical site each time the causative drug is given
51
What can vesicullobullous drug reactions be provoked by
Pencillamine
NSAIDs
Furosemide
Capropril
52
What can hyperpigmentation be
Extrinsic
| Intrinsic
53
When might Hypopigmentation occur
on the facial skin if corticosteroids are applied regularly or at too high a dose (can be permanent- ometimes see a ‘halo’ of depigmentation peri- orally after prolonged use of potent topical corticosteroid creams or ointments
54
What is Angioedema due to
Leaky capillaries resulting in increased permeability
55
What can Angioedema lead to
Protein leaching out into tissues taken fluid within —> orofacial swelling
This can compromise the airway
56
What is Angioedema an example of
Type I hypersensitivity reaction
57
What does Urticaria refer to
Raised wheals of concentric red and pale tissue swellings which are often itchy
58
What is gingival enlargement
Overgrowth of fibrous tissue of the gingival
59
Give examples of drugs that can cause gingival enlargement
1. Phenytoin
2. Calcium channel blockers
3. Valproate
60
A combination of causative drug and what can lead to a dramatic gingival reaction
Poor plaque control
61
What is hypo salivation
The objective reduction in saliva production
62
What is xerostomia
Percieved dry mouth
63
What is sialosis
enlargement of the major salivary glands
64
give examples of sensory abnormalities that can be caused by drugs
1. Dysaesthesia
2. Paraesthesia
3. Halitosis
65
What is Dysaesthesia
Abnormal sensation
66
Which drugs can cause Dysaesthesia
Metronidazole, metformin and sertraline which cause a metallic taste
ACE-inhibitors can cause an impairment in taste perception or oral mucosal burning
67
What is Paraesthesia
the feeling of pins and needles
68
What can cause Paraesthesia
1. Chemotherapy agents like vincristine
| 2. Labetalol- a beta blocker
69
What is Halitosis
Smelly breath
70
What drugs can cause Halitosis
1. Isosorbide dinitrate tablets
| 2. General impairment of saliva production leads to drying and overgrowth of organisms which give off an odour
71
Give examples of motor abnormalities that arise as a result of ADRs
1. Dyskinesia
| 2. Dystonia
72
What is Dyskinesia
An abnormality of voluntary movement
73
What is Dystonia
abnormal muscle tone
74
What does a full drug history include
1. When the drug was started and why
2. How symptoms of the suspected ADR developed in relation to taking the drug
3. Whether drug dose changes
