BASIC - ENDOCRINE Flashcards
Names of rapid acting insulin?
- Insulin Aspart (e.g. Novorapid)
- Insulin Lispro (Humalog)
- Insulin glulisine (Apidra)
Names of short-acting insulin?
- Humulin & Novolin Regular
Names of intermediate acting insulin?
- Humulin & Novolin N
Names of long-acting insulin?
- Insulin glargine (Lantus)
- Insulin detemir (Levemir)
Names of pre-mixed insulin?
- Humulin 70/30 & 50/50
- Novolin 70/30
- Humalog Mix 75/25
- Humalog Mix 50/50
- Novolog Mix 70/30
Indications of insulin?
Type 1 & 2 diabetes
IV in DKA and hyperglycaemic hyperosmolar syndrome
Perioperative glycaemic control in selected diabetic patients
Hyperkalaemia
Mechanism of insulin?
- Similar function to endogenous insulin
- Stimulates glucose uptake into skeletal muscle and fat
- Increases use of glucose as energy source
- Stimulates glycogen, lipid and protein synthesis
- Inhibits gluconeogenesis and ketogenesis
- Drives K+ into cells – short-term measure
Side effects of insulin?
Hypoglycaemia
SC injection – fat hypertrophy
Caution of insulin?
- Insulin clearance reduced in renal impairment (risk of hypoglycaemia)
Interactions of insulin?
- Combining insulin and other OHAs increase risk of hypoglycaemia
- Corticosteroids increases insulin requirements
How it insulin prescribed?
- Prescribed in units – normal daily requirements are 30-50 units
Symptoms of hypoglycaemia and how to treat?
- Hypoglycaemia, symptoms to watch out for (e.g. dizziness, agitation, nausea, sweating and confusion)
o Explain that, if hypoglycaemia develops, they should take something sugary (e.g. glucose tablets or a sugary drink) then something starchy
What is Basal bolus regimens?
Combination of 1/2 slow acting insulin before bedtime (glargine) with 3 injections of rapid acting insulin after/before meals (Humalog/Novorapid)
Can adjust for meals and infections better
Need to test sugars more, at school inject (psychological)
What is 2/3x day pre-mixed regimen?
Not suitable for kids’ normal daily activity
Difficult to control/change insulin dosages
What is continuous SC insulin pump?
Gives basal infusion and bolus when eat
Needle changed every 2-3 days
Cannot use in sports, swimming, baths (if disconnected – DKA)
Monitoring of insulin?
o Self-monitoring of blood glucose
At least 4 times a day, before meals and before bed
Targets – FPG 5-7 on waking, PG 4-7 before meals, PG 5-9 90 mins after eating
o HbA1c monitored regularly (at least annually)
Aim for HbA1c of 48 mmol/mol or lower
o If IV then serum K+ measured every 4 hours
Names of sulphonylureas?
Gliclazide
Indications of sulphonylureas?
Type 2 DM (2nd line single agent or in combination)
Mechanism of sulphonylureas?
- Stimulates pancreatic insulin secretion
- Block ATP-dependent K+ channels in pancreatic B-cell membranes and open voltage-gated Ca2+ channels
- Only effective in residual pancreatic function
- Weight gain
Side Effect of sulphonylureas?
- GI upset (nausea, vomiting, diarrhoea, constipation)
- Hypoglycaemia
- Cholestatic jaundice
- Rashes
- Agranulocytosis
Dose changes in renal and hepatic impairment of sulphonylureas?
o Dose reduction in liver and renal impairment
Caution of sulphonylureas?
o Malnutrition, elderly and hepatic impairment
Interactions of sulphonylureas?
- Risk of hypoglycaemia with other OHAs and insulin
- Efficacy reduced by prednisolone, thiazide and loop diuretics
Dose of sulphonylureas?
- Oral, SR/MR (different doses)
- Usually dose 40-80mg OD
- Long-term treatment so should not be stopped or changed
- Take with meals
Monitoring of sulphonylureas?
o HbA1c (target <53mmol/mol) o LFTs and U&Es before treatment
Indications of metformin (biguanide)?
Type 2 DM (1st choice) or used in combination with other OHA
Mechanism of metformin?
- Increases sensitivity to insulin
- Suppresses hepatic glucose production (glycogenolysis and gluconeogenesis), intestinal glucose absorption and increases glucose uptake by skeletal muscles
- Reduces weight gain (induce weight loss)
- Excreted unchanged by kidney
Side Effects of metformin?
- GI upset (nausea, vomiting, taste disturbance, diarrhoea)
- Lactic acidosis
o In illness, worsened renal impairment, increased lactate production and reduced lactate metabolism
Contraindications of metformin?
o Severe renal impairment (dose reduction in moderate)
o Withheld in AKI, tissue hypoxia, acute alcohol intoxication
Caution of metformin?
o Hepatic impairment
o Chronic alcohol overuse
o Other nephrotoxic drugs (NSAIDs, diuretics, ACEi)
Interactions of metformin?
- Withheld before and 48 hours after IV contrast media
- Prednisolone, thiazide and loop diuretics elevate blood glucose so oppose actions of metformin
Prescription of metformin?
- Oral tablet
- GI upset started at low dose and increased gradually
- Commonly 500mg OD with breakfast then increasing 500mg weekly to BDS
- Swallow tablets whole with glass of water with or after food
Monitoring of metformin?
Missed dose rules?
Aims according to HbA1c?
o HbA1c target 48mmol/mol
o U&Es before starting treatment, then at least annually
- If miss a dose, take ASAP unless near next dose
If >58 - intensify treatment
If on one OHA not associated with hypos - Aim 48mmol/L
If on drug associated with hypos - Aim 53mmol/L
Name of thiazolidinediones?
Pioglitazone
Indications of thiazolidinediones? (pioglitazone)
Type 2 DM (single agent where metformin not tolerated, second or third agent)
Mechanism of thiazolidinediones? (pioglitazone)
- Insulin sensitizers
- Activate nuclear PPARgamma which induces genes to enhance insulin action in skeletal muscle, adipose tissue and liver
- Increased peripheral glucose uptake and reduced hepatic gluconeogenesis
- Weight gain
Side effects of thiazolidinediones? (pioglitazone)
- GI upset, Anaemia, Dizziness, headache, disturbed vision
- Oedema and cardiac failure
- Bladder cancer
- Bone fractures
Contraindications of thiazolidinediones? (pioglitazone)
- Heart failure
- CVD
- Bladder cancer or macroscopic haematuria
Caution of thiazolidinediones? (pioglitazone)
- Smoking, occupational exposure
- Elderly
- Hepatic impairment (metabolised in liver)
Interactions of thiazolidinediones? (pioglitazone)
Other OHAs increase risk of hypoglycaemia
Prescription of thiazolidinediones? (pioglitazone)
- Oral
- 15-30mg OD with breakfast and can be increased
- Long-term treatment should not be stopped or changed
- Taken in morning with glass of water
Monitoring of thiazolidinediones? (pioglitazone)
o HbA1c before and 3-6 months after commencing
o LFTs before and during treatments
Names of thyroid hormones?
Levothyroxine, liothyronine
Indications of levothyroxine?
Levothyroxine, liothyronine
Mechanism of levothyroxine?
- Thyroid gland produces thyroxine (T4), which is converted into active triiodothyronine (T3) in target tissues
- Regulate metabolism and growth
- Levothyroxine (synthetic T4) is usual treatment. Liothyronine (synthetic T3) acts quick so used in emergency treatment of hypothyroidism
Side Effects of levothyroxine?
- Diarrhoea, vomiting, weight loss
- Palpitations, arrhythmias, angina, flushing
- Tremor, restlessness, insomnia
- Menstrual irregularities
Contraindications of levothyroxine?
o Thyrotoxicosis
o Pregnancy – may require increased dose – specialist care
Cautions of levothyroxine?
o Coronary artery disease (low dose starting), MI, HF
o Diabetes mellitus (dose of antidiabetic drug may need increasing)
o Hypopituitarism – need corticosteroid therapy before levothyroxine to avoid Addisonian crisis
Interactions of levothyroxine?
- GI absorption affected by antacids, calcium or iron salts
o Separate by at least 4 hours - Levothyroxine can change insulin or OHA requirements in diabetes
Prescription of levothyroxine?
o Oral initially 50-100 micrograms OD, adjusted in 25-50 microgram steps every 3-4 weeks to response
o Maintenance of 100-200 micrograms OD, taken >30 minutes before breakfast or coffee/tea
o If elderly or cardiac disease – initial 25 micrograms daily and adjust dose to maintenance of 50-200 micrograms
Monitoring of levothyroxine?
o Review patient monthly, dose changes guided by symptoms
o TFTs at 3 months after starting or a dose change
o Stable patients have annual review and TFTs
Indications of carbimazole?
- Hyperthyroidism
MEchanism of carbimazole?
- Thyroid gland produces thyroxine (T4), which is converted into active triiodothyronine (T3) in target tissues
- Regulate metabolism and growth
- Carbimazole reduces the amount of hormone released by thyroid
- Does not affect thyroxine already made and stored so takes 4-8 weeks to work
Side Effects of carbimazole?
- Nausea, vomiting, stomach upset
- Headache, muscle and joint pain
- Skin rash and itching
- Taste disturbances
- Bone marrow suppression
o Neutropenia and agranulocytosis
Report infective symptoms (sore throat), perform WBC if clinical evidence of infection
Stop promptly if neutropenia
Contraindications of carbimazole?
o Pregnancy – use contraception when on therapy (congenital malformations, especially first trimester)
o Severe blood disorders
o Severe liver disease
o Acute pancreatitis
Interactions of carbimazole?
- Risk of myelosuppression with other medication that causes this
- Warfarin enhances anticoagulant effects – additional monitoring needed
Prescription of carbimazole?
o 15-40mg OD continue until patient euthyroid, usually after 4-8 weeks
o Reduce dose gradually, therapy usually given for 12-18 months
Monitoring of carbimazole?
o Before treatment – FBC and LFT
o During treatment – TFTs every 4-6 weeks for first few months, then every 3 months
Patient communication of carbimazole?
o Report any infective signs (sore throat, mouth ulcers, bruising, fever, malaise)
o Advise against pregnancy on medication – use effective contraception
Names of glucocorticoids?
Prednisolone, hydrocortisone, dexamethasone
Indications of glucocorticoids?
Allergic or inflammatory disorders (anaphylaxis, eczema, asthma, COPD)
Severe croup
Autoimmune disease (IBD, ITP, inflammatory arthritis)
Cancer treatment
Myasthenia Gravis, Polymyalgia rheumatica, GCA, Lupus
Proctitis
Joint injections
Adrenal insufficiency/Hypopituitarism
MEchanism of glucocorticoids?
- Bind to cytosolic glucocorticoid receptors which upregulate anti-inflammatory genes and downregulate pro-inflammatory genes (cytokines, TNFa)
- Suppression of circulating monocytes and eosinophils
- Metabolic effects
o Increased gluconeogenesis
o Increased catabolism - Mineralocorticoid effects
o Stimulate Na and water retention and K excretion
Side Effects of glucocorticoids?
Immunosuppression Diabetes mellitus Insomnia, psychosis and suicidal ideas Osteoporosis Metabolic o Proximal muscle weakness, skin thinning with easy bruising and gastritis Mineralocorticoid o Hypertension, hypokalaemia and oedema Prolonged o Adrenal atrophy leading to Addisonian crisis if withdrawn suddenly
Cautions of glucocorticoids?
- Infection
- Children (suppress growth)
- Hepatic or Renal impairment
Interactions of glucocorticoids?
Risk of peptic ulceration – NSAIDs
Hypokalaemia – B2-agonists, theophylline, loop and thiazide diuretics
Affected by CYP450 enzymes
Prescription of glucocorticoids?
o Can be given orally, IM, IV
o OD, taken in the morning to mimic natural circadian rhythm
o Consider use of bisphosphonates and PPIs if long-term and risk
Monitoring of glucocorticoids?
o For children – height and weight monitored annually – refer to paediatrician if slow
o Prolonged treatment – HbA1c or DEXA scan
Cessation of glucocorticoids?
o Abrupt withdrawal can lead to adrenal insufficiency
o Gradual withdrawal used if treatment >3 weeks, received >40mg, repeated evening doses
Patient communication in glucocorticoids?
o Should feel better in 1-2 days
o Do not stop immediately
o Steroid card to carry round at all times
o If ill, double usual dose
