Endocrine System Flashcards
(51 cards)
Insulin
Mechanism of Action
Exogenous replacement of deficient hormone to stimulate glucose absorption, glycogenesis, lipogenesis, proteosynthesis and inhibit gluconeogeneis and ketogenesis, also increases K+ absorption and act in short, intermediate or long-term (biphasic = rapid and intermediate)
Insulin
Indications
T1DM, poorly controlld T2DM, DKA, peri-operative glycaemic control, hyperkalaemia
Insulin
Contra-indications
Reduced clearance proportionate to renal impairment (further renal imp req’s lower dose)
Insulin
Side Effects
Hypoglycaemia (coma/death), lipohypertrophy at injection site
Insulin
Interactions
Corticosteroids reduce effect
Sulphylurea
Name
Gliclazide
Sulphylurea (Gliclazide)
Mechanism of Action
Lowers blood glucose via stimulation of pancreatic insulin secretion - blocks ATP-dependent K+ channels in beta-cell membranes causing depolarisation - requires residual pancreatic function
Sulphylurea (Gliclazide)
Indications
T2DM - when metformin is C/I or combined if insufficient
Sulphylurea (Gliclazide)
Contraindications
Hepatic/renal imp, high risk of hypoglycaemia, T1DM, DKA, pre-coma/coma
Sulphylurea (Gliclazide)
Side effects
GI upset, hypoglycaemia, weight gain, hyponatraemia (SIADH), cholestatic hepatitis
Sulphylurea (Gliclazide)
Interactions
Other diabetic drugs
Drugs that increase glucose - steroid, thiazides, loops
Biguanide
Name
Metformin
Biguanide (Metformin)
Mechanism of action
Increases insulin sensitivity and glucose uptake in skeletal muscle, suppresses hepatic glucose production by AMPK activation
Biguanide (Metformin)
Indications
T2DM - first choice for control of blood glucose
Biguanide (Metformin)
Contraindications
Renal impairment, AKI, severe tissue hypoxia, acute alcohol intoxication, chronic overuse
Biguanide (Metformin)
Side effects
Lactic acidosis with severe liver/renal disease, GI upset (dose dep, common), reduced appetite, weight loss, vitamin B12 resorption
Biguanide (Metformin)
Interactions
IV contrast media (CKD/lactic acidosis risk), drugs that increase glucose, recent hypoxia (MI/sepsis)
Thyroid Hormones
Names
T3 - Liothyronine (active, IV use in emergency)
T4 - Levothyroxine (pro-hormone)
Levothyroxine
Mechanism of action
Agonist of thyroid receptors
Levothyroxine
Indications
Primary or Secondary (low TSH) hypothyroidism
Levothyroxine
Contraindications
CAD, hypopituitary state must initiate corticosteroid before thyroid therapy to avoid Addisonian crisis
Levothyroxine
Side effects
As Hyperthyroidism - GI, cardiac and neuro manifestations
Levothyroxine
Interactions
GI absorption reduced by antacids/Ca/Fe salts
CYP450 inducers reduce efficacy
Levothyroxine may change metabolism affecting insulin and warfarin
Anti-thyroid
Name
Carbimazole