Pharmacology 1 - Drug Eruptions (not finished)

Question 1

What is a drug eruption?

Answer 1

An adverse drug reaction of the skin

Question 2

What 2 factors play a role in deciding whether (and the time frame in which) a drug eruption will resolve when a drug is withdrawn?

Answer 2

Ability of drug to accumulate in tissue

1/2 life of drug

Question 3

Example of a type 1 immunologically mediated drug eruption?

Answer 3

Urticaria

Question 4

Example of a type 2 immunologically mediated drug eruption?

Answer 4

Pemphigus and pemphigoid

Question 5

Example of a type 3 immunologically mediated drug eruption?

Answer 5

Purpura

Question 6

Example of a type 4 immunologically mediated drug eruption?

Answer 6

Contact dermatitis

Question 7

Are immunologically mediated drug eruptions dose dependent?

Answer 7

No

Question 8

5 examples of non-immunological drug eruptions>

Answer 8

Drug-induced alopecia
Photo-toxicity
Skin erosion
Atrophy from topical steroids
Pigmentation
Many others

Question 9

6 presentations of drug eruptions?

Answer 9

Exanthematous/ morbilliform/ maculopapular (synonymous) - most common (75-95%)
Urticarial (5-10%)
Papulosquamous/ pustular/ bullous
Pigmentation
Photosensitivity
Itch/ pain

Question 10

What does an Exanthematous/ morbilliform/ maculopapular rash look like?

Answer 10

A diffuse and symmetric eruption of erythematous macules/ small pupules

Question 11

What is a papulosquamous rash?

Answer 11

Papules + scales

Question 12

Are young adults or infants/ elderly more likely to get a drug eruption?

Answer 12

Young adults

Question 13

Are males or females more likely to get a drug eruption?

Answer 13

Females

Question 14

What features of penicillin make it more likely to cause a drug eruption? (2)

Answer 14

B-lactam compounds

It is a haptem forming drug

Question 15

What is a haptem?

Answer 15

A molecule that illicits an immune response only when attached to a large carrier

Question 16

What 3 chemical features make a drug more likely to cause a drug eruption?

Answer 16

B lactam compounds
NSAIDs
High molecular weight/ haptem forming drugs

Question 17

Are mucous membranes usually affected in an Exanthematous/ morbilliform/ maculopapular drug eruption?

Answer 17

Usually spared

Question 18

What type of hypersensitivity is an exanthematous drug eruption usually?

Answer 18

Type 4

Question 19

Usual onset time of an Exanthematous/ morbilliform/ maculopapular drug eruption after taking drug?

Answer 19

4 - 10 days

Question 20

What features of an Exanthematous/ morbilliform/ maculopapular drug eruption rams indicate a potentially severe reaction? (3)

Answer 20

Blisters
Purpura
Necrosis

Question 21

What drugs are associated with an Exanthematous/ morbilliform/ maculopapular drug eruption? (9)

Answer 21

Sulphonamide antibiotics
Penicillin
Chloramphenicol
Streptomycin
Erythromycin

Phenytoin
Carbamazepine

NSIADs
Allopurinol

Question 22

What type of drug is phenytoin?

Answer 22

Anti-seizure drug

Question 23

What type of drug is chloramphenicol?

Answer 23

Antibiotic

Question 24

What type of drug is carbamazepine?

Answer 24

Anti-seizure drug