Insulin Flashcards
What is the MOA of insulin?
- Lowers blood glucose levels by INC uptake by skeletal muscles and adipose tissue
- Suppresses hepatic gluconeogenesis
When would you inc the dose of insulin?
- Infection or intercurrent illness
- Surgery, trauma
- Puberty, pregnancy (2nd/3rd)
When would you dec the dose of insulin?
- Red food intake, physical activity
- Renal impairment
- Endocrine disorder eg. Addison’s
How do you administer insulin?
SC: abdomen, thighs, buttocks + upper arm
- MHRA: cutaneous amyloidosis at injection site
Counselling:
- Rotate injection site to avoid lipodystrophy
- Check site for local injection site reactions: infection, swelling, bruising, lipodystrophy
- Do not miss meals, avoid strenuous exercise
- Recognise warning signs of hypoglycaemia
What are common insulin errors?
- Do not extract insulin from pen devices - severe harm + death w/drawing insulin from pen device
- Prescribe doses in UNITS or INTERNATIONAL UNITS – never event: OD due to abbreviation
- Never give IV syringe for SC injections
- Check injection technique
- Check insulin container, pen, or needle size
How is insulin stored?
Fridge 2-8°c
- Once opened: room temp, use by <28 days
- If frozen: discard
Short acting - soluble
- Onset: 30-60 min
- Duration: upto 9H
Eg. Human OR Beef/pork - Route: SC + IM
- IV: surgery or emergency
- 15-30 min before meals
- Consume <30min to avoid hypo
Rapid acting - analogue
- Onset: 15 min
- Duration: 2-5H
Eg. Aspart, Glulisine, Lispro - Route: SC
- IV: surgery or emergency
- Just before meals
- Lower risk of Hypo before meals + nocturnal
Intermediate acting - analogue
- Onset: 1-2H
- Duration: 11-24H
Eg. Isophane (NPH) - Route: IV = thrombosis
- Take BD
Long acting - analogue
- Duration: upto 36H
Eg. Degludec, detemir (BD), glargine (biologic – rx by brand), protamine zinc (IV = thrombosis) - Take OD at same time
Insulin regime: multiple injections
- Short OR rapid acting (before each meal) AND intermediate OR LA
- Pro: flexible dosing
- Con: more injections
- Counsel: match insulin dose according to carb intake
Insulin regime: biphasic
- Short OR rapid acting MIXED intermediate acting
- Pro: less injections
- Con: can’t take if intercurrent illness
- Counsel: regulate cab intake to match dose; immediately before meals
Insulin regime: Subcutaneous infusion
Short OR rapid CONTINUOUS (delivered by programmable infusion pump)
Insulin regime: type 1
First line: multiple injections
- Rapid acting + detemir BD
Alt: biphasic regimen BD
Subcutaneous infusion:
- Disabling, recurrent + unpredictable hypo
- Poor glycaemic control – HbA1c >8.5% (despite optimised MI)
- Children <12 (if MIR impractical)
Insulin regime: type 2
Basal only: human isophane (OD/BD)
Detemir/glargine:
- Need help injecting
- Would otherwise need BD injections
- Lifestyle restricted by hypoglycaemic episodes
Multiple injections/biphasic: human isophane AND short acting
Rapid acting:
- Prefers to inject before meals
- High post prandial glucose levels
- Hypoglycaemia is a problem
