Endocrinology

Question 1

Mechanism of action of insulin

Answer 1

Acts like endogenous insulin
STIMULATES:
-glucose uptake
-glycogen, lipid and pro. synth.
-K+ into cells

INHIBITS

• gluconeogenesis
• ketogenesis

Question 2

Types of insulin

Answer 2

RAPID
SLOW
INTERMEDIATE
LONG
BIPHASIC (Rapid + Int.)

Question 3

Indications for use of insulin

Answer 3

1. T1DM
2. T2DM
3. DIABETIC EMERGENCY
4. HYPOKALAEMIA

Question 4

Contraindications of the use of insulin

Answer 4

Patients with renal impairment can keep insulin in the system for longer which may = hypo

Question 5

Side effects of insulin

Answer 5

Mainly hypos

Adverse SC issues of constant injections

Question 6

Examples of sulfonylureas

Answer 6

Gliclazide

Question 7

Mechanism of action of sulfonylureas

Answer 7

Closes potassium channels and opens sodium channels at beta pancreatic cells which causes an influx of Ca = increase in insulin = lower glucose

Question 8

Indications of sulfonylureas

Answer 8

T2DM as the drug requires a residual pancreatic B cell function

Question 9

Contraindications of sulfonylureas

Answer 9

Any other drug which lowers glucose

Check patients that have hepatic and renal impairment

Question 10

Side effects of sulfonylureas

Answer 10

Hypoglycaemia

GI upset

Question 11

Metformin is an example of what drug class?

Answer 11

Biguanide

Question 12

Mechanism of action of metformin

Answer 12

Increases insulin sensitivity
Reduces hepatic production of glucose
Does not cause increased secretion of B Panc. Cells therefore no risk of hypoglycaemia

Question 13

Indications of metformin

Answer 13

First line treatment of T2DM

Question 14

Contraindications of metformin

Answer 14

Check in renal impairment. Do not prescribe in severe renal impairment
AKI
Hepatic impairment
Alcoholics

Question 15

Side effects of metformin

Answer 15

GI Upset

Lactic acidosis

Question 16

Interactions of metformin

Answer 16

Withhold before and after IV contrast therapy

Loop diuretics + Thiazides + Prednisolone counter the effects of metformin

Question 17

What type of drug is carbimazole?

Answer 17

Anti-Thyroid

Question 18

Mechanism of action of carbimazole

Answer 18

• Inhibits uptake and conc. of inorganic iodine
• Decreases formation of thyroxine
• Active form = methamizole: prevents action of thyroid peroxidase enzyme so reduces production of T3/4

Question 19

Indications and contraindications of carbimazole

Answer 19

Indications: hyperthyroidism

Contraindications: hepatic impairment, pregnancy, breast feeding

Question 20

Side effects of carbimazole

Answer 20

LMNOP

Liver dysfunction
Malaise and myalgia 
Nausea and neuritis
Occasional agranulocytosis 
Pruritus and psychosis

Question 21

Interactions of carbimazole

Answer 21

May enhance some anticoagulant effects

Question 22

Mechanism of action of thyroxine

Answer 22

Synthetic compounds with a similar structure to T4 and T3.

Levothyroxine: synthetic T4
Liothyronine: snythetic T3 (emergencies only)

Question 23

Indications of use for thyroxine

Answer 23

Hypothyroidism (primary or secondary)

Question 24

Contraindications of thyroxine use

Answer 24

CAD: can precipitate cardiac ischaemia so use a low dose

In hypopituitarism: give corticosteroids before thyroxine to avoid addisonian crisis

Question 25

Side effects of thyroxine

Answer 25

Similar to hyperthyroidism picture due to increased doses i.e. gastro upset, cardiac and neuro

Question 26

Interactions of thyroxine with other drugs

Answer 26

Absorption may be reduced by antacids, or salts so a gap of 4hrs is required

Question 27

What to inform the patient before they start taking thyroxine

Answer 27

It’s a replacement of a natural drug
It may take time to work
Do not overdose

Question 28

Examples of bisphosphonates

Answer 28

Alendronic acid

Pamidronate

Question 29

Mechanism of action of bisphosphonates

Answer 29

Structurally similar to natural pyrophosphate
Incorporated into bone during resorption
Osteoclasts inhibited and made inert
Bones become stronger

Question 30

Indications for use of bisphosphonates

Answer 30

Severe hypercalcaemia
Osteoporotic fragility fractures
Myeloma
Breast metastases to bone

Question 31

Contraindications of bisphosphonates

Answer 31

Do not give orally to anyone with GI problems
Severe hypocalcaemia
Smokers/dental disease due to risk of osetnecrosis of the jaw

Question 32

Side effects of bisphosphonates

Answer 32

Oesophagitis
Hypophosphatemia
Osteonecrosis of the jaw
Atypical femoral fracture

Question 33

Interactions of bisphosphonates

Answer 33

Salts inc milk can reduce absorption

Question 34

Indications for use of calcium and Vitamin D

Answer 34

1. Osteoporosis: ensures +ve Ca balance
2. CKD: prevent secondary hyperpara.
3. Severe hyperkalemia: prevent arrhythmia
4. Hypocalcemia
5. Vitamin D Deficiency

Question 35

Contraindications of using calcium and vit D

Answer 35

Hypercalcaemia

Question 36

Side effects of calcium and vit D

Answer 36

Dyspepsia
Constipation
Cardiovascular collapse
Local tissue damage

Question 37

Indications for use for a coritco-steroid

Answer 37

1. allergic reactions
2. hormone replacement in adrenal insufficiency / hypopituitarism
3. depress autoimmune diseases
4. some cancer treatments

Question 38

Mineralocorticoid mechanism of action

Answer 38

Stimulate Na and H20 retention and K excretion in the renal tubules

Question 39

Immune response effects of corticosteroids

Answer 39

Upregeluate anti-inflammatory genes and down regulate pro-inflammatory genes

Question 40

Metabolic effects of corticosteroids

Answer 40

Increase gluconeogensis from circulating amino and fatty acids

Question 41

Side effects of cotricosteroids

Answer 41

1. Immunosuppression
2. Metabolic: DM, osteoporosis
3. Mood and behavioural changes
4. HTN, low K and oedema

Question 42

Interactions of corticosteroids

Answer 42

Increase risk of ulcers w/ NSAID

Increase hypokalaemia in patients w/ beta agonists

Efficacy reduced by cytochrome p450 inducers