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
