S15) Steroid Pharmacology

Question 1

Identify the different layers of the adrenal cortex

Answer 1

Question 2

Identify some different types of corticosteroids, including examples

Answer 2

• Glucocorticoids e.g. cortisol
• Mineralocorticoids e.g. aldosterone
• Sex steroids

Question 3

Outline the HPA axis

Answer 3

Question 4

Identify six metabolic actions of glucocorticoids

Answer 4

• Glycogenolysis
• Gluconeogenesis
• Hyperglycaemia
• Proteinolysis
• Lipolysis (low conc.) / lipid deposition (high conc.)
• Redistribution of fat

Question 5

Identify five effects of glucocorticoid deficiency

Answer 5

• Hypoglycaemia
• Weight loss
• Nausea
• Hypotension
• Underweight

Question 6

Identify five effects of glucocorticoid excess

Answer 6

• Hyperglycaemia
• Weight gain
• Increased appetite
• Hypertension
• Cushingoid

Question 7

Identify four effects of mineralocorticoid deficiency

Answer 7

• Hyponatraemia
• Dehydration
• Hypotension
• Hyperkalaemia

Question 8

Identify three effects of mineralocorticoid excess

Answer 8

• Hypernatraemia
• Hypertension
• Hypokalaemia

Question 9

Describe the pharmacokinetics for corticosteroids

Answer 9

• High oral bioavailability (diffuse easily)
• Metabolised by liver, eliminated by kidney
• Hepatic and renal clearance (decreases with age)

Question 10

Identify the various different routes of administration for steroid drugs and provide an example drug for each

Answer 10

• Intravenous e.g. methylprednisolone
• Oral e.g. prednisolone
• Inhaled e.g. beclomethasone
• Topical e.g. betamethasone
• Intra-articular e.g. triamcinolone

Question 11

Describe five effects of corticosteroids on the immune system

Answer 11

• Inhibition of B and T cell responses
• Reduced phagocytic function
• Immunosuppression
• Reduced inflammation
• Reduced transcription of cytokines

Question 12

Briefly, describe the mechanism of action of steroid hormones

Answer 12

Question 13

What are the clinical uses of steroid drugs?

Answer 13

• Inflammatory disease
• Immunosuppression
• Malignancy
• Adrenal insufficiency
• Cushing’s disease diagnosis

Question 14

What are the indications for corticosteroid replacement therapy?

Answer 14

• Deficiency
• Addison’s disease
• Adrenolectomy

Question 15

Which drugs can be used for corticosteroid replacement therapy and what is their dosage?

Answer 15

• Hydrocortisone (cortisol) 20 - 30 mg daily
• Fludrocortisone (aldosterone) 50 - 300 μg daily

Question 16

Which inflammatory diseases are treated by corticosteroids?

Answer 16

• Asthma
• GI disease
• Nephrotic syndrome
• Rheumatoid arthritis
• Inflammatory skin conditions

Question 17

Describe the use of steroids in pregnancy

Answer 17

A single course of antenatal corticosteroids is offered to women who are at risk of preterm birth (24-34 weeks of gestation)

Question 18

Which steroids are given to women at risk of preterm birth?

Answer 18

• Betamethasone 12 mg given IM in two doses
• Dexamethasone 6 mg given IM in four doses

Question 19

What are the side effects of mineralocorticoids?

Answer 19

• Fluid retention
• Hypertension
• Hypokalaemia

Question 20

What are the side effects of glucocorticoids?

Answer 20

• Osteoporosis
• Avascular necrosis
• Peptic ulcers
• Increased infections
• Hypertension
• Diabetes

Question 21

Describe the Cushingoid fat distribution

Answer 21

Question 22

What are the effects of corticosteroid on bone?

Answer 22

• Inhibition of osteoblast formation
• Increased osteoclast proliferation
• Reduced calcium absorption in gut
• Reduced sex steroid production
• Osteoporosis

Question 23

How does adrenal suppression occur?

Answer 23

• Suppression of HPA axis occurs after 3 weeks
• Prednisolone > 20 mg will suppress HPA axis
• May persist for years, if long term treatment

Question 24

What precipitates a hypo-adrenal crisis?

Answer 24

Abrupt withdrawal of steroids

Question 25

What characterises a hypoadrenal crisis?

Answer 25

• Hypotension
• Hypoglycaemia
• Hyponatraemia
• Hyperkalaemia
• Severe dehydration
• Death, if untreated