Steroids Flashcards
What is the role of the Medulla?
- Secretes catecholamines (part of ANS)
- Secretes A and NA
What is the role of the Cortex?
- Secretes mineralcorticoids, glucocorticoids, cortisol and adrenal sex hormones
List the Adrenal Hormones
- Glucocorticoids
- Mineralcorticoids
- Androgens
What is the role of Glucocorticoids?
- Cortisol
- increases blood pressure and blood sugar level and reduces immune responses
What is the role of Mineralcorticoids?
- Aldosterone
- hormone that causes the tubules of the kidneys to retain sodium and water
- increases volume of fluid in the body, drives blood pressure up
- part of RAAS
- hormone that causes the tubules of the kidneys to retain sodium and water
What is the role of Androgens?
- DHEA
- natural steroid precursor of testosterone with some activity of its own
- testosterone (produced by testes and adrenals)
Physiological Effects of Adrenocortical Steroids
What is Glucose Metabolism’s Effect on the Body?
- Stimulates gluconeogenesis
- Decreases glucose use by tissues
Physiological Effects of Adrenocortical Steroids
What is Protein Metabolism’s Effect on the Body?
- Increases breakdown of protein
- Increases plasma protein levels
Physiological Effects of Adrenocortical Steroids
What is Fat Metabolism’s Effect on the Body?
- Increase of mobilsation of fatty acids
- Increase of use of fatty acids
Physiological Effects of Adrenocortical Steroids
What is Anti-Inflammatory action and Immunosuppression Effect on the Body?
- Stabilise lysosomal membranes in inflammatory cells preventing release of inflammatory mediators
- Decrease of capillary permeability to prevent oedema
- Depresses phagocytosis
- Suppresses atrophy of lymphoid tissue
- Decreases fever
- Suppresses immune response
- Inhibits fibroblast activity
Physiological Effects of Adrenocortical Steroids
What is Psychological Effect on the Body?
- Contribute to emotional instability
Physiological Effects of Adrenocortical Steroids
What is Permissive Effect on the Body?
- Facilitates the response of the tissues to humoral and neural influences during trauma and extreme stress
What is the role of the Hypothalamus-Pituitary-Adrenal Axis?
- Cortisol feedsback to the hypothalamus to control release of CRH
- High levels of cortisol in the blood inhibit release of CRH by the hypothalamus, consequently less ACTH is released by the anterior pituitary, which in turn, causes less cortisol to circulate in the blood
What effects can stress have on the Hypothalamus-Pituitary-Adrenal Axis?
What is HPA a key factor in?
- Stress can have immunosuppressive effects and the hypothalamus-pituitary-adrenal axis (HPA) is a key factor in the neural modulation of the immune system
Describe the Anti-Inflammatory and Immunosuppresive Effects of Glucocorticoids
- Decrease in number of eosinophils, lymphocytes and monocytes
- Decrease leukocyte migration and phagocytic activity
- Decrease production of phospholipase A2, prostaglandins, thromboxanes and leukotrienes
What are the Clinical Uses of Glucocorticoids?
- Replacement Therapy
- For glucocorticoid deficiency: hydrocortisone
- For mineralcorticoid deficiency: fludrocortisone
- Anti-inflammatory
- Short acting: hydrocortisone
- Intermediate acting: prednisolone
- Long-acting: dexamethasone
- Immuno-suppression
- Treatment of Allergic Disorders
What are the Adverse Effects of Glucocorticoids?
- Suppression of HPA
- Cushing’s Disease (Excess)
- Psychological and behavioural changes, aggravation of pre-existing psychiatric disorders
- Impaired wound healing
- Osteoporosis, muscle weakness and atrophy
- Fluid retention, oedema, hypertension
- Increased acid and pepsin secretion
What does an Excess of Glucocorticoids lead to?
- Cushing’s Syndrome
What does a Deficiency of Glucocorticoids lead to?
Describe this Disease
- Addison’s Disease
- Primary (Addison’s)
- caused by adrenal gland disease
- associated with all 3 hormones deficiency
- rare disease, most often caused by auto-immune mediated destruction of adrenal cortex
- Secondary
- caused by ATCH deficiency
- associated with glucocorticoid deficiency
What are the symptoms of Addison’s Disease?
- Hypoglycaemia
- Weight loss
- Weakness
- GI
- Bronze pigmentation
- Postural hypotension
What are other effects of Glucocorticoids?
- Growth and cell division
- inhibit cell division or synthesis of DNA
- delay the process of healing
- retard the growth of children
What are the long term Adverse Effects of Glucocorticoids?
- Glucose intolerance
- Acne
- Hypertension
- Oedema
- Susceptibility to infection
- Myopathy
- Cataract
- Peptic Ulcer
- Suppression of HPA axis
Describe the Precautions that can be taken to minimise the Adverse Effects of Long-Term steroid therapy
- Modification of Dose/Dose regimen
- use short course/low doses
- use steroid sparing drugs (anti-inflmmatories of non-steroid types such as NSAIDs)
- withdraw ‘chronic’ steroids slowly
- give one dose once daily in morning
- give on alternate days
- give dose locally
What is the process of withdrawal?
- ‘Cold Turkey’ if glucocorticoid therapy was shorter than 2 weeks
- Taper off if glucocorticoid therapy was longer than 2 weeks
- Rate of taper should be proportional to duration of therapy
- The longer the original therapy, the slower the rate of dose reduction
Restoration of HPA axis is the reason
What are Withdrawal Effects of Glucocorticoids?
- Addisonian Crisis
- Hypotension
- Muscle tenderness
- Hypoglycaemia
- Myalgia and Fatigue
- Fever
- Joint Pain
- Muscle Stiffness
