Cutaneous Drug Eruptions

Question 1

Roughly what percentage of adverse drug reactions are cutaneous

Answer 1

30%

Question 2

The skin is a common target for what type of drug reactions

Answer 2

Idiosyncratic drug reactions

Question 3

Why are drug reactions under reported

Answer 3

Not all patients with a reaction will go to their doctor

Question 4

What is a type 1 allergic reactions

Answer 4

Urticaria

Question 5

What is a type 2 reactions

Answer 5

Pemphigus and pemphigoid

Question 6

What is a type 3 reactions

Answer 6

Purura/ Rash that can’t be blanched

Question 7

What is a type 4 reaction

Answer 7

T cell mediated. Erythema / rash

Question 8

Immunologically -mediated reactions are dose dependent. True or False

Answer 8

False

Question 9

Non-immunologically mediated reactions are dose dependent. True or false

Answer 9

True

Question 10

Give some examples of non-immunologically mediated reactions

Answer 10

Eczema 
Drug-induced alopecia (chemotherapy)
Phototoxicity
Psoriasis
Pigmentation
Cheilitis
Xerosis

Question 11

A patient complains of burning/ tingling sensation when they are out in the sun. What is the diagnosis

Answer 11

Photosensitivity

Question 12

How does a skin eruption usually resolve?

Answer 12

When the drug is withdrawn

Question 13

Who is more at risk of developing a drug eruption? Males or females?

Answer 13

Females

Question 14

What type of drugs are higher risks for drug eruptions

Answer 14

B lactam compounds, NSAIDS

High molecular weight/ hapten-forming drugs

Question 15

What 3 things should be considered in a patient on multiple drugs?

Answer 15

A drug that is known to be most likely to cause an eruption
The time interval between exposure and development of skin reaction
History of previous exposure to the same drug

Question 16

What is the most common type of drug eruption

Answer 16

Exanthematous

Question 17

What type of reaction is an Exanthematous drug eruption

Answer 17

Type 4

Question 18

Describe the usual appearance of an exanthematous drug eruption

Answer 18

Widespread symmetrically distributed rash

Pruritus and fever are also common

Question 19

After how long does the reaction occur

Answer 19

4-21 days after first taking the drug

Question 20

What are some indicators of a potentially severe reaction

Answer 20

Involvement of mucous membrane and face
Facial oedema and erythema 
Widespread confluent erythema 
Blisters
Shortness of breath
Wheezing

Question 21

Name some drugs which are associated with Exanthematous drug eruptions

Answer 21

Penicillins 
Sulphonamide antibiotics
Erythromycin
Streptomycin
Allopurinol
Anti-epileptics
NSAIDs
Phenytoin

Question 22

Which immunoglobulin is usually associated with an Urticarial drug reaction

Answer 22

IgE (Type 1 )

Question 23

Glucocorticoids can sometimes causes what type of drug eruption

Answer 23

Steroid acne

Pustular / Bullous drug eruption

Question 24

What types of drugs can cause drug induced bullous pemphigoid

Answer 24

ACE inhibitors
Penicillin
Furosemide

Question 25

Describe the apearance and locaation of fixed drug eruptions

Answer 25

Well demarcated round/ ovoid plaques.
Red, painful
Hands, genitalia, lips, oral mucosa (occcasionally)

Question 26

What drugs are associated with fixed drug eruptions

Answer 26

Tetracycline, doxycycline
Paracetamol
NSAIDs
Carbamazepine

Question 27

What type of light is usually a concern for phototoixc cutaneous drug reactions

Answer 27

UVA/ Visible

Question 28

Name some drugs associated with phototoxicity

Answer 28

Antibiotics
Thiazidde diruetics 
Chloropromazine
NSAIDs
Psoralens
Amiodarone
Immunosuppressants

Question 29

What information about a drug reaction is required

Answer 29

The timing of symptoms to time of administration
When did the drug start/ stop
Photo of reaction
Why was the drug being taken
Drug history
Previous history of drug reactions/ allergy

Question 30

What is the management for a patient with a drug reaction

Answer 30

Discontinue the drug is possible - use another one
Topical steroids may be useful
Antihistamines may be useful
Allergy bracelets
Report via the Yellow card scheme (medicines and healthcare products regulatory Agency)