Corticosteroids

Question 1

Describe the route of administration and examples of corticosteroid drugs

Answer 1

• Examples of glucocorticoid drugs include hydrocortisone, prednisolone, dexamethasone
  
  • Most have both glucocorticoid and mineralocorticoid actions, but with differing ratios
• Can be given orally, IV, inhaled, topical, intra-articular

Question 2

Describe the mechanism of glucocorticoid action

Answer 2

• Glucocorticoids diffuse through cell membrane and bind to glucocorticoid receptor within the cytoplasm or nucleus, which upregulates the expression of anti-inflammatory proteins (transactivation)
• Also reduce activation of pro-inflammatory mediators and cytokines (transregression)
• Inhibition of T cells and B cells act as immunosuppressant mechanism helping in hypersensitivity reactions

Question 3

Describe the spectrum of steroid uses in multiple disease states

Answer 3

• Inflammatory disease - asthma, COPD, inflammatory skin conditions, haematological diseases
• Immunosuppression - rheumatoid arthritis, lupus
• Malignancy
• Adrenal insufficiency (replacement therapy) -Addison’s disease
• Cushing’s disease diagnosis

Question 4

Describe the mineralocorticoid side effects

Answer 4

• Fluid retention
• Hypertension
• Hypokalaemia

Question 5

Describe the glucocorticoid side effects

Answer 5

CORTICOSTEROIDS

• Cushing’s syndrome - central obesity
• Osteoporosis - inhibition of osteoblast formation and increased osteoclast proliferation
  
  • Reduced calcium reabsorption in gut
• Retardation of growth
• Thin skin, easy bruising
• Immunosuppression - increased risk of infection
• Cataracts and glaucoma
• Oedema
• Suppression of HPA axis - adrenal suppression
• Teratogenic
• Emotional disturbances
• Rise in BP
• Obesity
• Increased hair growth
• Diabetes
• Striae

Question 6

Describe how potency relates to half life with reference to glucocorticoids

Answer 6

• The greater the potency, the greater the half life
• Short acting corticosteroids (hydrocortisone) have a small half life and potency
  
  • Given in higher doses compared to other corticosteroids as least potent (greatest concentration needed to issue response)
• Intermediate acting corticosteroids - prednisolone
• Long acting corticosteroids - dexamethasone

Question 7

Describe monitoring and withdrawal of long-term corticosteroid treatment

Answer 7

• Adrenal suppression - by giving corticosteroids, it suppresses the HPA axis
  
  • Withdrawal symptoms occur if high dose prednisolone treatment suddenly stopped - hypoadrenal crisis
  • Hypotension, hypoglycaemia, hyponatraemia, hyperkalaemia, severe dehydration, death if untreated
• Gradual withdrawal of oral prednisolone needed