Drug Eruptions

Question 1

What type of drug reaction occurs on the skin?

Answer 1

idiosyncratic drug reactions

Question 2

Give an example of type 1, 2, 3 and 4 immunologically-mediated reactions?

Answer 2

1 = anaphylaxis 
2 = Cytotoxic reactions
3 = immune complex delayed hypersensitivity reactions (purpura/rash)
4 = cell mediated delayed HR, T-cell mediated (erythema/rash)

Question 3

Name two chemicals that can be involvedin drug eruptions

Answer 3

Beta-Lactam

NSAIDS

Question 4

What is the most common type of drug eruption?

Answer 4

Exanthematous (90%)

Question 5

What hypersensitivity reaction is involved in exanthematous drug eruptions?

Answer 5

Type 4

Question 6

How long does a Exanthematous drug reaction usually take to occur?

Answer 6

4-21 days

Question 7

What indicators are there of severe exanthmatous reactions?

Answer 7

Mucous membrane/face involvement,
facial oedema & erythema,
Widepsread confluent erythema,
fever above 38.5,
blisters, purpura, necrosis,
lymphodenopathy, arthalgia,
SoB and wheezing

Question 8

Name some drugs involved in exathematous DE

Answer 8

penicillins, NSAIDs, erythro/stroptomycin, allopurinol, anti-epileptics, phenytoin, chloamphenicol, sulponamide antibiotics

Question 9

Describe Urticarial DE

Answer 9

usually immediate IgE-mediated (type 1)

Question 10

What causes inflammatory mediators from mast cells on 1st exposure in urticarial reactions?

Answer 10

Exposure to aspirin, opiates, NSAIDs, muscle relaxants, vancomycin, quinolones.

Question 11

What causes an IgE-mediated type 1 Urticarial reaction?

Answer 11

rechallenge with drugs (B-Lactams antibiotics, carbazepine + many others)

Question 12

What can cause Pustular or Bollous drug eruptions in a) Acne and b) Acute Generalised exanthematous pustulosus (AGEP)

Answer 12

a) glucocorticoids, androgens, lithium, isoniazide, phenytoin
b) antibiotics, calcium channel blockers, antimilarials

Question 13

What drugs cause bollous pemphigoid?

Answer 13

ACEi, penicillin and furosemide

Question 14

What drug can cause Linear IgA disease?

Answer 14

Vancomycin

Question 15

Name two cutaneous adverse reaction

Answer 15

Stevens-Johnson Syndrome

Toxic epidermal necrolysis

Question 16

What can both Chlorpromazine and Amioderone both cause?

Answer 16

immediate prickling with delayed erythema and pigmentation

Question 17

What drugs can exacerbate a sunburn?

Answer 17

Quinine, thiazides, DCMT

Question 18

What drug causes a delayed erythema and pigmentation of 3-5 days?

Answer 18

psoralens

Question 19

What drugs cause increased skin fragility?

Answer 19

Nalidixic acid, tetracycline naproxen, amiodarone

Question 20

Where should drug eruptions be reported to?

Answer 20

Yellow card scheme (Medicines and Healthcare products Regulatory Agency)

Question 21

How may skin reactions be treated?

Answer 21

topical steroids,
antihistamines
Allergy bracelets