Ph- Antidiabetic drugs Flashcards
What are the rapid-acting bolus insulins?
- lispro
- aspart
- glulisine
noLAG
What is the short-acting bolus insulin?
regular insulin
What is the intermediate-acting basal insulin?
NPH
iNtermediate
What are the long-acting basal insulins?
- glargine
- detemir
[for a LONG time i am going to have GLARing DEbT]
What are the 5 classes of oral agents for diabetes?
- sulfonylureas
- thiozolidinediones
- biguanides
- DPP-IV Inhibitors
- SGLT2 inhibitors
What are the 3 sulfonylurea oral antidiabetic agents?
What is the mechanism of action of sulfonylureas?
What patients use these drugs?
How are they delivered?
- glyburide
- glipizide
- glimepiride
MOA: stimulate insulin secretion from B-cells by binding to and inhibiting ATP-sensitive K channel.
These drugs are only useful in type 2 diabetics with functioning B-cells. Delivered orally 1-2x /day
What drug is the thiozolidinedione [TZDs] oral antidiabetic agent?
What is the mechanism of action?
pioglitazone [Thio, pio]
MOA: improves insulin sensitivity in peripheral fat, muscle by binding to and activating PPARs [TFs that regulate FA metabolism].
- TZDs differentiate pre-adipocytes to adipocytes with increased storage for fast subcutaneously.
- redistribute fat storage from muscle, liver, heart and pancreas to subcutaneous sites
- direct effect to improve liver insulin sensitivity
What drug is the biguanide oral antidiabetic agent?
metformin
What oral antidiabetic drug is the DPP-IV inhibitor?
sitagliptin
What oral antidiabetic drug is the SGLT2 inhibitor?
canagliflozin
What is the glucagon-like peptide modulator?
GLP analog = liraglutide
How is insulin synthesized and secreted?
- Synthesis: as a single chain preprohormone within the B-cells of the islet of langerhans
- Processing: into a a molecule with disulfide linked alpha and beta chains by carboxypeptidase. C-protein is released.
- Storage: in secretory vesicles in B cells until stimulus provokes it to release into hepatic circulation
How does the concentration of insulin differ from portal circulation and systemic circulation?
Insulin is 50-100microns/ml in portal circulation compared to 12 microns/ml systemically.
This concentration differential is NOT achieved with insulin replacement therapy
How much insulin is secreted per day for a normal pancreas?
What are the 2 phases by which it is released?
What is each phase required for?
The loss of which phase is one of the earliest defects in type 2 DM?
Pancreas normally secretes 25-30 units a day
Phase 1 = priming phase. Burst of secretion with food that occurs within the first 10 minutes.
This is required for:
1. normal hepatic sensitivity to insulin
2. normal body glucose homeostasis
Phase 2 = slower, delayed phase. Insulin is secreted over several hours after the first phase.
This is required for:
1. long term glucose control
Loss of phase 1 is one of the first defects in DM2
What is the difference between bolus dosing and basal dosing for insulin therapy?
What insulins are used for each type?
Bolus dosing is used to imitate the first phase of glucose secretion. It is given coinciding with meals to limit post-prandial hyperglycemia.
-rapid acting [lispro, aspart, glulisine] OR short-acting [normal insulin]
Basal dosing is used to maintain steady state insulin levels by suppressing glucose between meals and overnight.
- longer-acting = [glargine, detemir]
- intermediate = NPH
What is the goal of basal-bolus treatment?
It attempts to mimic normal kinetics of insulin secretion by combining a long/intermediate insuling with a rapid/short acting insulin.
For basal-bolus treatments, which can come premixed?
Which must be given as 2 separate injections?
Premixed:
- NPH and regular insulin
- NPH and [lispro, aspart, glulisine]
Theses are fixed ratios and are NOT flexible
Glargine cannot be combined physically with any other insulin prep and must be given as a separate injection
What about the structure allows rapid-acting insulins to be rapid-acting?
What are they given to treat?
What is the most commonly used preparation?
They have a mutation that makes them like normal insulin with a less stable hexamer. This makes them:
- readily soluble
- rapidly absorbed
They are given to treat post-prandial hyperglycemia and should be administered 5-10min before the meal.
The most common preparation is insulin pump
When should normal insulin be given?
30 minutes before the meal. You need to be careful that you actually eat the meal though, and eat as much as you had expected or else it can lead to hypoglycemia
When is NPH used to treat hyperglycemia? What are the two ways it can be delivered?
It is an intermediate-acting insulin and is used basally. Give it 2x daily.
The two ways it can be delivered are:
- premixed with rapid or short acting insulin in a fixed ratio
- mixed with rapid/short acting insulin just prior to administration in a flexible ratio
A patient comes in to refill a perscription of insulin. You ask which one they are on and they reply “I don’t know. The cloudy one.”
What insulin are they on? Why is it cloudy?
NPH and it is cloudy because it is mixed with protamine to reduce solubility.