Drug Reactions, Adverse Reactions and Allergies

Question 1

How are drugs pharmacologically developed?

Answer 1

1) Serendipity: By random chance e.g. Penicillin

2) Rational Drug Design e.g. propanolol

Question 2

What is drug development?

Answer 2

Process of bringing new pharmaceuticals to market

Question 3

What is drug re-purposing?

Answer 3

Technique where existing drugs are used to treat emerging and challenging diseases

Question 4

How does rational drug design come about?

Answer 4

Process of developing an antagonist from an agonist by looking at solubility, electrostatic charge and bulk

Question 5

What 3 things do the chemical properties of a drug influence?

Answer 5

1) Elimination
2) Distribution
3) Administration

Question 6

What 4 receptors do drugs target?

Answer 6

1) Kinases
2) Ligand Ion Channels
3) GPCR
4) Cytosolic/Nuclear

Question 7

What is gene therapy?

Answer 7

Experimental technique using genes to either treat or prevent disease

Question 8

What are 3 examples of gene therapy?

Answer 8

1) Replace a mutated gene with a healthy copy
2) Inactivate a gene that isn’t correctly functioning
3) Introduce a new gene into the body to help fight a disease

Question 9

What are the pharmacokinetic issues of immunotherapy? (3)

Answer 9

1) Immunoglobulin: Not filtered by the kidneys
2) FcRn receptor: Absorb IgG into cells to protect them from metabolism
3) Mouse AB’s: Not substrates for human FcRn (have half the half-life)

Question 10

What are the 3 types of Antibody?

Answer 10

1) Polyclonal: Non-specific foreign protein e.g. antilymphocyte globulin
2) Monoclonal: Single specificity
3) Humanised: Non-self issues

Question 11

Define an adverse drug reaction?

Answer 11

Noxious and Unintended response to a drug

Question 12

What are the 6 types of Rawlins-Thompson adverse reactions?

Answer 12

1) Type A (Augmented Pharmacological)
2) Type B (Bizarre/Idiosyncratic)
3) Type C (Chronic)
4) Type D (Delayed)
5) Type E (End of Treatment)
6) Type F (Failure of Therapy)

Question 13

What are the events and treatment of a Type A reaction?

Answer 13

Augmented, very common, dose related and predictable physiological effects from drug
TREATMENT: Reduce the dose

Question 14

What are the events and treatment of a Type B reaction?

Answer 14

Bizarre, unpredictable, immunological mechanisms and hypersensitivity, (History of allergy)
TREATMENT: Immediately withdraw the drug

Question 15

What are the events of a Type C reaction?

Answer 15

Chronic, occurs after long term therapy

Question 16

What are the events of a type D reaction?

Answer 16

Delayed, occurs many years after treatment

Question 17

What are the events of a type E reaction?

Answer 17

End of use, withdrawal of drug after long use (complications of stopping med.)

Question 18

What is idiosyncrasy?

Answer 18

An inherent abnormal response to a drug

Question 19

What are some common ADRs?

Answer 19

Constipation, Diarrhoea, Nausea, Hypotension

Question 20

What are yellow cards?

Answer 20

Voluntary reporting system for ADRs

Question 21

What does a black triangle represent?

Answer 21

A medicine undergoing additional monitoring (All routine medicines only reported for SERIOUS reactions)

Question 22

What happens in each of the 4 hypersensitivity reactions?

Answer 22

1: IgE becomes attached to mast cells and cross-links -> Mast cell degranulation -> Histamine release
2: IgG mediated cytotoxicity
3: Immune complex deposition: Not cleared by innate immune system –> Inflammatory response
4: T cell mediated

Question 23

What are the main features of anaphylaxis?

Answer 23

1) Rapid onset
2) Blotchy rash
3) Swelling of lips and face
4) Wheezing
5) Hypotension
6) Cardiac Arrest

Question 24

What is non-immune anaphylaxis?

Answer 24

AP from direct mast-cell degranulation from non previous exposure e.g. drug reaction