Endocrine drugs Flashcards
(34 cards)
What are the 3 methods of action of insulin?
Stimulates glucose uptake to tissues from circulation
Stimulates glycogen, lipid and protein synthesis, and inhibits gluconeogenesis and ketogenesis
Drives K+ from bloodstream into cells (short term)
Give 4 indications of insulin
T1DM: replacing endogenous insulin
T2DM: For control when oral isn’t enough
Diabetic emergencies eg ketoacidosis
Hyperkalaemia along with glucose
What effect does renal impairment have on insulin dosages?
Reduce dose as less insulin clearence, so more risk of hypos
Name one major and one minor sde effect of insulin use
Major:Hypos!
Minor: fat growth around overused injection site
Name a sulphonurea
Gliclazide
How does gliclazide work?
Stimulates pancreatic insulin secretion.
What kind of diabetics can gliclazide be used effectivley in, and who can’t it be used it?
Requires residual pancreatic beta cell function, so it can only be used in type 2 diabetics with pancreatic function
Can’t be used in type one of end stage type 2
When would gliclazide be prescribed?
T2DM 2nd line
What are some side effects of gliclazide
GI upset eg nausea, vomiting
Hypos
Rare hypersensitivity reaction
What kind of drug is metformin? When is it prescribed?
Bigluanide
Type 2 diabetes, first line
How does metformin work?
Lowers blood glucose by increasing the sensitivity to insulin
Increases glucose uptake and utilisation by skeletal muscles and supresses intestinal glucose absorbtion
Doesn’t increase pancreatic insulin secretion
When wouldn’t metformin be used?
Severe renal impairment
AKI
Severe hypoxia
Acute alcohol intoxication (can precipitate lactic acidosis)
Name 2 interactions with metformin
CT contrast: withold 48hours before and after due to nephrotoxicity, reduces insulin clearence so more chance of hypos
Prednisolone, thiazide and loop diuretics raise BMs
Name 1 common and one rare side effect of metformin
GI upset
rare: lactic acidosis
How does levothyroxine work?
Replaces lost T4
Why shouldn’t levothyroxine and antacids, calcium, or iron salts be given within 4 hours of each other
Affect levothyroxines GI uptake
Why would you need to take more levothyroxine if yu were also on phenytoin or carbemazepine?
They are cytochrome p450 inducers, which break down levothyroxine
Carbemazepine or carbimazole: Which is which?????
Carbemazepine: antiepileptic cytochrome p450 inducer
Carbimazole: antithyroid
How does carbimazole work?
Converted to methimazole, which prevents the thyroid peroxidase enzyme from coupling tyrosine residues in thyroglobulin, stoping T3 and T4 production.
When is carbimazole contraindicated?
Severe blood disorders and hepatic insufficiency
What is an interaction of carbimazole?
Vitamin K antagonist, so can have an effect on anticoagulants
Name a bisphosphonate and describe their method of action
Alendronate
Reduce the amount of bone turnover by limiting osteoclastic activity (absorbed by them, they then signal for apoptosis)
Give 3 indications for alendronic acid
OSteoporosis
Bone mets in breast Ca (reduce risk of fractures)
Pagets disease of bone
Also hypercalcaemia of malignancy
When is alendronic acid contraindicated?
severe renal impairment
hypocalcaemina
oral administration contraindicated in upper GI disorders
