Insulin Flashcards
What are common indications for insulin therapy?
- Type 1 and type 2 diabetes
- DKA
- HHS
- Hyperkalaemia
What is the mechanism of action of insulin?
- Increases glucose uptake by insulin-sensitive tissues (e.g. adipose, muscle)
- Increases glycogen synthesis in muscle and liver
- Increases amino acid uptake into muscle
- Increases protein synthesis
- Increases triacylglycerol synthesis in adipocytes and liver i.e. stimulates lipogenesis and inhibits lipolysis
- Inhibits the enzymes of gluconeogenesis in the liver
- Promotes K+ ion entry into cells
What are examples rapid acting insulins?
- Novorapid
- Apidra
- Humalog
When are do you need to be cautious with insulins?
- Renal impairment
- Hepatic impairment
- Pregnancy and breastfeeding
What are examples of intermediate acting Insulins?
- Novomix 30
- Humalog Mix25
- Humulin I
- Insulatard
What are examples of long acting insulins?
- Lantus
- Levemir
What are examples of short-acting insulins?
- Actrapid
- Humulin S
When is the peak effect of novorapid?
Within 10-20 minutes of administration
When is the peak effect of humalog?
15 minutes of administration
When is the peak effect of actrapid?
2-4 hours
When is the peak effect of humulin S?
30 minutes to 2.5 hours
When is the peak effect of insulatard?
45 mins - 12 hours
When is the peak action of Humulin I?
45 mins - 8 hours
When is the peak effect of humulin mix 25?
20 minutes - 2.5 hours
What type of insulin are novorapid 30 and humilin mix25?
Biphasic insulin - rapid + intermediate acting
When should analogue mixtures be administered?
Just before/during/after food
When should rapid acting insulins be administered?
Just before/during/after meals
When should short acting insulins be administered?
20-45 mins before food
When should long-acting insulins be administered?
Once/Twice a day, at the same time every day
What is a three times daily regimen?
Mix of short and intermediate acting before breakfast, short acting before lunch, and intermediate at bedtime
What is a basal bolus regimen?
Long acting mix once daily with short acting insulin before meals
What is a twice daily regimen?
Mix of short and intermediate acting given before breakfast and tea
What insulins are used in a twice daily regimen?
Premixed e.g. Novomix 30 or Humalog mix25
What is the normal daily requirement of insulin?
30-50 units - varies substantially between individuals
How is insulin given in diabetic emergencies?
50 units of actrapid diluted in 50 ml 0.9% saline - 1unit/ml
How would youa administer insulin in hyperkalaemia?
10 units Actrapid added to 20% glucose 100mls and infused of 15 minutes
What are adverse side effects of insulin therapy?
Hypoglycaemia
Injection site
- Lipodystrophy
- Rashes
- Transient oedema
How is insulin cleared?
Kidneys
If insulin is given as an infusion, what should you monitor?
K+ at least every 4 hours
Why should you avoid giving actrapid to treat unexpected high blood glucose concentration?
Time to peak effect (2-3 hours) is longer than commonly appreciated, and trying to correct hyperglycaemia quickly is often unnecessary and can be dangerous. Instead, try to understand why hyperglycaemia has occured, and make small alterations to regimen
