ENDOCRINOLOGY DRUGS Flashcards
what kind of hormone is insulin?
peptide
what 3 processes does insulin stimulate or inhibit?
glucose transport from circulation into fat and muscle cells
Stimulates glycogen, protein and lipid synthesis
inhibits gluconeogenesis and ketoacidosis
What are the uses of insulin?
Insulin replacement in DM1
Control of blood glucose levels DM2
IV for diabetic emergencies such as:hyperglycaemic hyperosmotic non-ketotic coma, ketoacidosis and perioperative glycaemic control
emergency hyperkalaemia treatment = moves k into the cells
what 3 forms of insulin are available?
short <7hrs
Intermediate 14-22hrs
Long acting >24 hrs
give 2 endocrine side effects of insulin
hypoglycaemia leading to coma and death
low plasma potassium (promotes K influx into cells)
give 2 other side effects of insulin
weight gain
fat hypertrophy at injection site
why shouldn’t beta blockers be given with insulin?
mask warning signs of a hypo
give an example of a sulphonylurea?
When do you use it?
Gliclazide, Glibenclamide, Tolbutamide
DMT2 control glucose levels and prevent complications
Single agent when Metformin is not working
Combination therapy with metformin when single agent is not enough.
You need residual pancreatic function ( B cells) for it to work
how do sulphonylureas work? (2 processes)
Stimulates pancreatic insulin production by binding to
sulphonylureas receptors &; blocking ATP dependent K channels on Pancreatic B cells= cause depolarisation which opens voltage gated Ca channels leading to increase in Ca level and insulin release
Inhibit glucogensis
what other diabetes meds are often combined with sulphonylureas?
metformin
why should sulphonylureas be used with caution in elderly patients or those with adrenal, pituitary, hepatic or renal impairment?
susceptible to hypos
why shouldn’t sulphonylureas be used with fluconazole?
fluconazole increases plasma conc of sulphonylureas?
give an example of a biguanide.
What is the function of the drug?
metformin which increasing insulin sensitivity but requires presence of insulin
how does metformin work? (3 processes)
increases peripheral glucose usage
inhibits gluconeogenesis and glycogenolysis ( impairs hepatic glucose production)
inhibits glucose absorption from GI tract
why is metformin good to use in obese patients?
suppresses appetite ( Induces weight loss)
give 3 examples of conditions predisposing to lactic acidosis that contraindicate use of metformin
hepatic/renal impairment (AKI) heart failure/ respiratory failure and Mi (tissue hypoxia) infection dehydration acute alcohol intoxication
What diabetic emergency should metformin not be used in?
Keto acidosis
Iv injection of what drug should lead to the stopping of metformin prior and for 48 hours afte the injection?
IV injection of iodine contrast= as it can lead to renal impairement and therefore lactic acidosis
When is thyroid hormone used and how does it work?
Primary hypothyroidism or secondary hypothyroidism to hypopituitarism
mimics endogenous thyroxine by converting t4 to T3
Give examples of thyroxine and when they are used?
Levothyroxine (synthetic T4)= long duration = commonly used
Liothyronine (synthetic T3) = short and fast acting so used in emergencies
What are the side effects of giving thyroxine?
Mimics symptoms seen in hyperthyrodism
such as restlessness, sweating, weight loss, cardiac dysrhythmias and tachycardia
why shouldn’t thyroxine be taken in conjunction with warfarin?
increases effect of warfarin
give an example of an anti-thyroid drug
carbimazole (main choice)
propylthiouracil (alternative)
Iodine and iodide
Propanolol
how do anti-thyroid drugs work?
decrease production of T3/T4 in thyroid gland
what enzyme do anti-thyroid drugs inhibit?
thyroid peroxidase - necessary for synthesis
how long should Grave’s anti-thyroid treatment last for?
more than 1 year
give an example of a bisphosphonate
alendronic acid, disodium pamidronate, zoledronic acid
how do bisphosphonates work?
inhibit osteoclast mediated bone reabsorption so promote bone development
sufficient levels of what two things are required in the body for bisphosphonates to work?
calcium and vitamin D
name 5 conditions that bisphosphonates are used in?
Name the specific drug used for the condiiton
- Osteoporosis = AL
- Post menopausal osteoporosis =al
- Corticosteroid induced osteoporosis =al
- Paget’s disease
- Hypercalcaemia of malignancy = dis and zol
- Bone mets from breast cancer and myeloma = dis and zol = to prevent bone fracture and cord compression
give a contraindication for the use of bisphosphonates
Upper GI tract problems as they have side effect oesophageal irritation
Hypocalcaemia
Renal impairment
why shouldn’t antacids, calcium or iron salts be used with bisphosphonates?
decrease absorption
give 3 examples of when calcium requirements in life increase
childhood
pregnancy
lactation
when does calcium absorption decrease?
elderly
when is the dose of calcium required to be doubled?
osteoporosis
what organ impairments can cause vitamin D deficiency?
liver
kidneys
give 2 contraindications of calcium and vitamin D supplements
hypercalcaemia
malignant/metastatic calcification
What drugs absorption is reduced when given with oral calcium?
Iron, bisphosphonates, tetracycline and levothyroxine
why should diuretics be used with caution with calcium supplements?
increase risk of hypercalcaemia
what should happen to the dose of vitamin D if carbamazepine or phenytoin are also being taken?
increased - they increase the body’s requirement for Vit D
give an example of a mineral corticoid
fludrocortisone
how do mineral corticoids work?
replacement of aldosterone in Addison’s or adrenal hypoplasia
Control the synthesis of proteins
how do mineral corticoids work in the kidneys?
Act on DCT to inhibit loss of sodium by increasing loss of potassium and hydrogen via urine.
give 2 examples of when mineral corticoids are used
adrenocorticol insufficiency
salt-losing adrenal syndrome
what type of systemic infection contraindicates use of mineral corticoids?
fungal
give 3 circulatory side effects of mineral corticoids
oedema
hypertension
cardiac enlargement
congestive cardiac failure
give 3 endocrine side effects of mineral corticoids
hypokalemia
cushing’s
growth suppression
menstrual abnormalities
give 3 other side effects of mineral corticoids
weakness papilloedema vertigo cataracts glaucoma impaired healing Pancreatitis and peptic ulcers
why shouldn’t mineralocorticoids be used with potassium depleting diuretics
hypokalaemia
why shouldn’t mineralocorticoids be used with digoxin?
increases risk of toxicity
why shouldn’t mineralocorticoids be used with oral anticoagulants?
decrease prothrombin time (reduces efficacy)
why shouldn’t mineralocorticoids be used with anti-diabetic drugs?
diminish effect
why shouldn’t mineralocorticoids be used with aspirin?
increase risk of ulcers
Besides lactic acidosis what other side effects does metformin have?
Diarrohea
Nausea and vomiting
Anorexia
How is metformin eliminated?
Tublar secretion of renal
What are the side effects of carbimazole?
Nausea , rash, pruritis, headache, mild GI disturbances, fever and malaise
Rare: Jaundice and BM suppression
What side effects do you get with bisphosphonates?
GI s/e
Such as abdo pain and disturbance
Oesophageal reaction
Hypophosphataemia
What are the S/E of Vit D and Ca on GI?
D&V
Conspitation
Weight loss/anorexia
What are the calcium supplement side effects?
Bradycarida
Arrythmia
What are the reanl S/E of supplements?
Polyuria, thirst
What organ impairment would be contradictory to give insulin?
Renal impairement
Having systemic corticosteroids does what to the insulin requirement?
Increase insulin requirement
What diabetic emergency should sulphonylureas be avoided in?
Diabetic ketoacidosis
What group of people should sulphonylureas not be given to?
Obese patients due to side effect of weight gain
What affect does chloramphenicol or NSAIDS have on sulphonylureas?
Increase the hypoglycaemic effect
Why shouldn’t you give sulphonylureas in pregnant ladies or when they are breast feeding?
Neonatal hypoglycaemia
What drugs reduce the effectiveness of sulphonylureas and metformin?
Drugs that have hyperglycaemic effect= Loop and thiazide diuretics and prednisolone
What drugs can damage renal function and therefore be used cautiously with metformin?
Diuretics
ACE inhibitors
NSAIDS
What is a rare but fatal side affect of metformin?
Lactic acidosis
What cardiovascular condition is contradictive to use of thyroxine and why?
CAD due to cardiac iscahemia
In hypopituitarism how do you administer corticosteroids and thyroxine?
First give corticosteroids and then thyroid hormones as can precipitate addisons crisis
What drugs reduce GI absorption of thyroid hormones?
Antacids, calcium and iron salts
What effect does thyroxine have on diabetes?
Need greater insulin and other oral hypoglycaemic drugs
Why shouldn’t carbimazole be used in pregnant/breast feeding patients?
Cause neonatal goitre or hypothyroidism
What is a severe side effect of anti thyroid drugs?
Bone marrow suppression causing neutropenia and agranulocytosis
What symptom is a complication of agranulocytosis caused by anti thyroid drugs?
Sore throat
What is the treatment for thyrotoxic crisis? emergency condition
Iv fluid, propranolol, hydrocortisone, iodine and carbimazole
What is propranolol used for in thyroid treatment?
Rapid relief of thyrotoxicosis symptoms
Treatment of neonatal thyrotoxicosis or SVA caused by hyperthyroidism
What are two rare side effects of bisphosphonates
Osteonecrosis of the jaw
Atypical femoral fracture
In which patient should use of bisphosphonates be used cautiously due to increase risk of osteonecrosis of the jaw?
Smokers
Patients with dental disease
How long should bisphosphonates be used for?
3 years
When is calcium and vitamin D used?
Both for osteoporosis
Both for CKd to treat and prevent secondary hyperparathyroidism and renal osteodystrophy
Calcium for severe hyperkalemia to prevent arrhythmias
Calcium for symptomatic calcium deficiency
VItamin D for prevention and treatment for vitamin D deficiency such as rickets in children and osteomalacia in adults
What side effects can you get with oral calcium?
Dyspepsia and constipation
What does the adrenal gland do?
Secretes hydrocortisone (cortisol) which has glucocorticoid affects and weak mineralocorticoid effects. Also secretes aldosterone
What is the combination treatment of insufficiency of the adrenal gland?
hydrocortisone and fludrocortisone
What is a potential side effect of calcium gluconate when given for hyperkalaemia?
if given too fast then can cause cardiac collapse
Can cause local tissue damage if given S/C
Does metformin cause hypoglycaemia? Explain why?
It does not cause hypoglycaemia because it does not have an affect on promoting insulin production from pancreatic B cells
Why is calcium essential?
For normal function of bones, nerves, muscles and clotting system
What controls calcium haemostasis?
Parathyroid hormones and vitamin D
What vitamin changes occur in CKD?
Impared phosphate excretion and reduced activation of vitamin D causes hyperphosphataemia and hypocalcaemia.
What does abnormal vitamin levels cause in CKD?
Leads to hyperparathyroidism leading to renal osteodystrophy
