Drug Allergies and Reactions

Question 1

What is the main lethal cause of Type 1 reactions?

Answer 1

Asphyxia

Question 2

Discuss the drug absorption mechanism of Type 2 reaction

Answer 2

Drug binds to the membrane. Antibodies are formed to the drug and cell toxicity occurs.

Question 3

Discuss the innocent bystander mechanism of Type 2 reaction

Answer 3

Antibodies and drug form a complex in the serum, which binds to the membrane. Complement is activated and the cell lysed.

Question 4

What is the main clinical presentation of Type 2 reacions?

Answer 4

Hemolysis or thrombocytopenia. Onset depends on whether or not the patient has been exposed before.

Question 5

What are the clinical presentations of Type 3 reactions?

Answer 5

Joint pain, serum sickness, vasculitis. Onset depends on if there was prior exposure.

Question 6

What are the clinical presentations of Type 4 reactions?

Answer 6

Rash, Eczema. Onset about 7-20 days

Question 7

Describe the procedure for an anaphylactoid reaction

Answer 7

1. Rechallange
2. Safely give chemically related compounds
3. Lower dose upon re-exposure

Question 8

Define an Adverse drug reaction.

Answer 8

A response to a drug that is noxious and unintended that occurs at normal doses.

Question 9

Define an Adverse drug event.

Answer 9

An injury resulting from the use of a drug.

Question 10

What is the course of management for Category A or C ADR/ADE?

Answer 10

Reduce dose or withhold the drug

Question 11

What is the course of management for Category B and D ADR/ADE?

Answer 11

Withdraw the drug

Question 12

What is an idiosyncratic reaction?

Answer 12

An ADR that is unpredictable, Not explained by the properties of the drug, Not an allergy or an anaphylactoid reaction.