Metabolic Flashcards
Name the 4 indications for insulin treatment
- insulin replacement in T1DM
- control of blood glucose in T2DM, where oral hypoglycameics fail to control adequately
- given IV in diabetic emergencies
- alongside glucose to treat hyperkalaemia
- What is the onset, peak and duration of action of rapid acting insulin?
- Name 2 examples
- onset within 5-15 mins; peaks after 30mins; cleared after 5 hours
- Novorapid; Humalog (lispro)
- What is the onset, peak and duration of action of short acting insulin?
- how is absorption into plasma delayed?
- Name 3 examples
- onset within 30 mins; peaks at 2-4 hours; duration 6-8 hours
- soluble; when injected, aggregates into hexamers
- actrapid; Humulin S; Insuman rapid
Name an example of intermediate acting insulin
Isophane/NPH insulin
- What is the onset of action of long acting insulin?
- What is long acting insulin used as?
- Name 3 examples of long acting insulin
- 4 hours
- background insulin
- lantus; levemir; insulin degludec
What insulins are used in combination in Biphasic insulin?
short and intermediate acting insulins
- Describe the multiple daily injection insulin regimen
2. What is it used for?
- long acting insulin + short acting bolus at meal time
2. most T1DM
- Describe the biphasic insulin regimen
2. What is it used for?
- biphasic insulin administered BD
2. T2DM or T1DM incapable of using multiple daily injection regimen
- Describe the long acting once daily insulin regimen
2. What is it used for?
- Long acting insulin administered OD
2. T2DM with concurrent oral hypoglycaemics
- Describe the continuous subcutaneous insulin infusion regimen
- What is it used for?
- continuous insulin infusion plus boluses at mealtimes. Closest to physiological insulin
- patients with T1DM who are unable to use multiple or biphasic regimens, or those with hypo-awareness
Name 4 adverse effects of insulin therapy
- risk of hypoglycaemia
- rebound hypoglycaemia following hypos (results from compensatory release of adrenaline)
- hypokalaemia (IV insulin)
- Weight gain and lipid hypertrophy around injection site
What are the 5 steps of T2DM management outlined by NICE?
- LIFESTYLE MODIFICATION
- diet
- weight control
- exercise
- MONOTHERAPY
- metformin
- DUAL THERAPY
- metformin + sufonyluria/sitagliptin/piaglitazone/gliflozin
- TRIPLE THERAPY
- metformin + sulfonylurea + another
- Insulin therapy
- What is the MOA of metformin?
- Name 2 advantages of metformin therapy
- What is the affect of metformin on weight?
- Name a contraindication of metformin therapy
- Name 2 adverse effects of metformin therapy
- acts on liver to reduce gluconeogenesis therefore reduces hepatic insulin resistance
- rarely causes hypos; reduces micro and macrovascular risk
- weight neutral
- renal impairment (avoid if eGFR <30)
- GI side effects (often poorly tolerated)
lactic acidosis
- What is the MOA of sulfonylureas?
- Name 2 examples of sulfonylureas?
- What is the affect of sulfonylureas on weight?
- Name an adverse effect of sulfonylureas?
- Why should alternatives to sulfonylureas be considered in patients with poor treatment compliance?
- act on beta cells to produce insulin (secretologues) - requires functional beta cell mass; eventually effect decreases
- gliclazide; glipizide
- weight gain
- hypoglycaemia
- requires multiple daily dosing
- What is the MOA of Pioglitazone?
- what is the effect of pioglitazone on weight?
- Name 3 adverse effects of pioglitazone
- PPARgamma agonist - promotes expression of GLUT4 and insulin receptors
- weight gain
- fluid retention (contraindicated in HF)
small bone fractures
increased risk of bladder cancer
Describe the incretin effect
Incretins - GLP-1 and GIP are produced in response to oral glucose
they have a potentiating effect on pancreatic insulin secretion
they are degraded by DPP-4
the incretin effect is diminished in T2DM
- What is the MOA of DPP-4 inhibitors?
- Name an example of a DPP-4 inhibitor?
- what is the effect of DPP-4 inhibitors on weight?
- Name 3 cautions to the use of DPP-4 inhibitors?
- enhance the incretin effect by preventing the degradation of incretins
- sitagliptin
- weight neutral
- acute pancreatitis
renal dysfunction
gastroparesis
- What is the MOA of SGLT2 inhibitors?
- Name an example of an SGLT2 inhibitor
- Name advantages of SGLT2 inhibitors (3)
- When are these drugs contraindicated?
- inhibits renal SGLT2 therefore prevents the reabsorption of glucose from the renal filtrate
- gliflozin
- weight loss
diuretic effect - improved BP and CV risk
reduced HbA1c - renal impairment (GFR <40)
- Why can it be difficult to control blood glucose in diabetic patients perioperatively?
- How is this achieved?
- patients are nil by mouth
- give variable rate insulin + glucose
maintain long acting insulin treatment
What are the sick day rules for insulin therapy? (3)
- continue long acting insulin; may need to adjust dose of short acting insulin
- drink/sip clear sugar free fluids to prevent dehydration
- check urine for ketones
- Which drug should be prescribed as soon as a diagnosis of hyperthyroidism is made?
- What does this drug do in hyperthyroidism?
- Beta blockers
- ameliorate symptoms caused by increased beta adrenergic tone
inhibit peripheral conversion of T4 to T3 (high doses)
Which drug is indicated for treatment of hyperthyroidism?
Carbimazole
- What is the MOA of carbimazole?
- What are the 2 treatment regimens of carbimazole?
- Name a contraindication for carbimazole therapy?
- thyroid peroxidase inhibitor - reduces synthesis of T3/T4
- titration therapy
block and replace therapy - Pregnancy - teratogenic
(contraception should be used in women undergoing carbimazole therapy)
- Which drug is used as an alternative to carbimazole in pregnancy?
- When in pregnancy should a switch from this drug to carbimazole be considered and why?
- Propylthiouracil
2. second and third trimesters due to risk of hepatotoxicity with propylthiouracil
What is the MOA of propylthiouracil?
prevents peripheral conversion of T4 to T3
Name a potentially serious side effect of carbimaxole and propylthiouracil therapy
Neutropenia and agranulocytosis
- patients should report symptoms suggestive of infection
- WCC should be performed if there is any clinical evidence of infection
- carbimaxole should be stopped promptly if there is clinical or laboratory evidence of neutropenia
- What drug is used in the treatment of Hypothyroidism?
- Name 5 drugs which can interfere with its absorption?
- What types of drugs affect its metabolism?
- Levothyroxine
- iron; calcium carbonate; mineral suppliments; colestyramine; sucralfate
- hepatic enzyme INDUCERS (phenobarbitol, phenytoin, carbamazepine; rifampicin)