INSULIN REGIMENS Flashcards
MOA of insulin
- Secreted by b-cells
- Increases glucose uptake by adipose tissue and muscle
- Suppresses hepatic glucose release
- Decreases blood glucose conc to prevent hyperglycaemia
How is insulin administered and why?
- Administered via subcutaneous injection
- Because insulin is inactivated by Gl enzymes
- It should be Injected into a body area with plenty of subcutaneous fat (abdomen or inner thigh)
- Abdomen has the fastest absorption rate
What can occur as a result of repeatedly injecting into the same small area?
LIPOHYPERTROPHY
- poor absorption of insulin = poor control
- ROTATE
- Signs of infection: swelling, bruising and lipohypertrophy
Types of insulin regimens
1.Basal-bolus insulin regimens
2.Biphasic regimen
3.Continuous subcutaneous insulin infusion (insulin pump)
T1DM - first line treatment
Basal bolus regime
- 3 bolus injections of rapid acting insulin for meals
- Once-twice daily background long acting insulin
What are the THREE categories of insulin preparation?
- Short-acting
- Includes “Soluble-Insulin” and “Rapid-acting” insulin - Intermediate-acting
- Long-acting
Basal
Long/ intermediate acting insulin
OD or BD
1. detemir BD
2. second line = glargine OD
List the different types of long-acting insulins?
- Insulin detemir
- Levemir - Insulin glargine
- Abasaglar
- Lantus
- Toujeo - Insulin degludec
- Tresiba
How often are long-acting insulins administered?
OD
- Insulin glargine (e.g. Abasaglar, Lantus, toujeo)
- Insulin degludec (e.g. Tresiba)
OD/BD
- Insulin detemir (e.g. Levemir)
Long-acting insulin’s pharmacokinetics
- Onset: 2-4 days to reach steady state
- Duration: 36 hours
Long-acting vs
Intermediate acting
- Both provide basal insulin
- But long-acting has a longer duration of action then intermediate (up to 36 hours)
Intermediate acting insulin’s
pharmacokinetics
- Onset: 1-2 hours
- Peak affect of 3-12 hours
- Duration: 11-24 hours
Given in conjunction with short acting, can be mixed or pre-mixed (biphasic)
Which Insulin is
intermediate-acting?
- Isophane insulin
- It is a suspension of insulin with protamine
What are the brands for Isophane insulin?
- Humulin I
- Insulatard
- Insuman
I for Intermediate-acting!
Which insulins mimic endogenous basal insulin sectretion?
- Intermediate-acting
- Long-acting
What are the types of short acting insulin?
Soluble (short-acting) insulin
Rapid-acting insulin
Describe the time-profile of short-acting insulins?
- They have a short duration of action
- And a relatively rapid onset of action
- it is used to replicate the insulin normally produced by the body in response to glucose absorbed from a meal
Short-acting: Soluble insulin’s
pharmacokinetics
Inject: 15-30 mins before meals
Onset: 30-60 mins
Peak action: 1-4 hours
Duration: up to 9 hours
If injected IV, then it has short t1/2 and onset of action instantaneous
When is IV soluble insulin mainly used?
- In diabetic emergencies e.g.
DKA - It is the most appropriate insulin to use in DKA
Give examples of Soluble insulin brands?
- Human Actrapid
- Humulin S
- Insuman Rapid
- Insuman Infusat
- Hypurin Bovine/Porcine neutral (Animal)
Short-acting: Rapid-acting insulin’s pharmacokinetics
Inject: immediately before meal
Onset: < 15 mins
Duration: 2-5 hours
Lower risk of hypo than soluble (short acting)
Alternative to soluble in emergency
What are the different types of rapid acting-insulin? Give examples of brands
- Lispro (Humalog Kwikpen)
- Aspart (NovoRapid, Fiasp)
- Glulisine (Apidra)
LAG = doesn’t LAG
Rapid-acting vs soluble insulin
Rapid:
- faster onset
- improved glucose control, reduction of HbA1c, and hypos
Soluble:
- longer duration
When should short-acting insulin be administered?
- Before meals!
- When given during or after meals, it is associated with poorer glucose control so therefore should be avoided
Which insulins mimic the endogenous bolus insulin secretions (meal-time insulin)?
Short-acting:
- Soluble insulin
- Rapid-acting analogous
Which short-acting insulin is NOT found pre-mixed with
isophane insulin as a biphasic preparation?
- Insulin Glulisine (e.g. Apidra)
Which insulins mimic the endogenous bolus insulin secretions (meal-time insulin)?
Short-acting:
- Soluble insulin
- Rapid-acting analogous
What formulations are available for insulin preparations?
- Pre-filled pens (throw away whole pen when finished)
- Cartridges (to put in a pen which you always have but change cartridge when they finish)
- Vial (where you get a syringe and draw it out of a vial)
Why should some insulins never be given IV
Particulate matter in suspension may lodge in the capillary beds of the lungs and the brain, leading to thrombus development
Biphasic insulin
- 1, 2 or 3 insulin injections per day of short acting MIXED with intermediate acting insulin
- Preps may be mixed by pt or pre-mixed
- More convenient
- Less control as proportions are fixed
Acutely ill patients on biphasic insulins
- Can’t use these biphasic mixtures to boost their insulin levels
- Should ideally have short or rapid-acting insulins to use to manage their insulin requirement whilst being ill.
Which insulins are found pre-mixed with Isophane insulin as biphasic preparation?
- Insulin aspart
- NovoMix 30 - Insulin Lispro
- Humalog Mix25
- Humalog Mix50 - Soluble insulin
- Humulin M3
- Insuman Comb 15
Continuous subcutaneous insulin infusion (insulin pump)
Regular or continuous amount of insulin (usually rapid acting insulin analogue or soluble insulin) delivered by a programmed pump and insulin storage reservoir via SC needle or cannula
When would you give continuous subcutaneous insulin infusion (insulin pump)
- Disabling hypoglycaemia
- Glycaemic control >8.5% despite optimised MIR
- Children over 12 (MIR is impractical) BUT they must undergo MIR trial between 12-18
What factors require pt to decrease insulin administration?
- Physical activity
- Reduced food intake
- Impaired renal function
- Certain endocrine disorders (thyroid, coeliac, Addison’s)
- Immediately after birth
When do insulin requirements increase?
- Infections or intercurrent illness
- Stress
- accidental surgical trauma
- Puberty
- Pregnancy - 2nd/3rd trimester
SIT PP
