Insulin and Oral Hypoglycemics Flashcards
Where is insulin made?
In what form is it made and what are the steps to become insulin?
made in the beta cells of Islets of Langerhans
Preproinsulin->proinsulin->insulin+C-peptide
Insulin leads to increased synthesis of _________, _________., and ___________
glycogen, protein and fatty acid
Insulin decreases glucose phosphorylation in cells. t/f
F, it enhances phosphorylation
Name 5 metabolic processes insulin decreases
Glycogenolysis gluconeogenesis ketogenesis lipolysis protein catabolism
what is the main function of insulin?
carry glucose across cell membrane?
Aside from monitoring glucose during an insulin infusion, what other lab is important to consider?
potassium
insulin drive K intracellular
Insulin is made of 2_________, joined by 3 ___________.
amino acid chains
disulfide bonds
Endogenous insulin is metabolized by kidney and liver, and ____% first pass
50
What is the duration of action of endogenous insulin
30-60 minutes
What is the basal rate of insulin production
1 u/hour
up to 40 u/day
What is onset, peak, and duration of Fast acting insulin?
What’s an example?
Lispro
Onset 5-15 min
peak 1 hour
Duration: 4-5 hours
What is onset, peak, and duration of regular insulin?
Onset: 30 min
Peak 2-3 hours
Duration 6-10 hours
What is onset and duration of NPHt’s an example?
Isophane
Onset 2-5 hours
Duration 10-20 hours
Variable peak
What is onset and duration of Long acting insulin?
What’s an example?
Ultralente
Onset: slow
duration prolonged: 16-20 hours
What are guidelines for insulin preoperatively?
cut A.M. insulin in half or cut all of it
DM pts should be first case of the day
or start an IV and check glucose as soon as they come in
What is the real long acting insulin that doesn’t have much of a peak
glargine/lantus
give 3 examples of bolus insulins and 4 basal insulins
Bolus: regular, humalog/lispro, Novolog/aspart (Apidra/glulisine)
Basal; NPH, Lente, Ultralenta, lantus/glargin (Levemir/detemir)
________ (Bolus/Basal) insulin more accurately reflects endogenous insulin
Bolus
What are uses of regular insulin?
Abrupt onset of hyperglycemia
Ketoacidosis
Hyperkalemia
What does NPH stand for?
Neutral protamine hagedorn
Hagedorn was a danish guy who created NPH insulin
How does protamine affect subQ insulin?
slows subQ absorption
How much protamine in is nph insulin?
0.005 mg/u
What is the calculation for basal dose or infusion of insulin?
(glucose-100)/40
What is the calculation for a bolus dose of insulin?
glucose/150
1 U of insulin lows blood glucose ___________mg/dL
25-30
What are the side effects of insulin?
Hypoglycemia!!!!! Allergic rxn Lipodystrophy resistance drug interactions
What are initial symptoms of hypoglycemia?
Diaphoresis
tachycardia
hypertension
What is the allergic reaction to insulin etiology?
Immune reactions are rare, it is usually a local allergy
protamine
What is lipodystrophy?
Loss of fat from one area
Lump or small dent in the skin that forms when a person performs injections repeatedly in the same spot.
Can cause rejection or slowed absorption of injected medication
Rotate injection sites
What drugs do insulin interact with?
Epinephrine-inhibits insulin release MAO Inhibitors-inhibits pancreatic islets Antibiotics -tetracycline-inhibits insulin release Salicylates-increase insulin release
HOw do sulfonylureas work?
Stimulate insulin secretion
hypoglycemia is a risk
How do meglitinides work?
stimulate insulin secretion
hypoglycemia is a risk
How do biguanides work?
Inhibit glucose production by liver
metformin
What are the alph-glucosidase inhibitors?
Slows digestion and absorption of carbohydrates
acarbose
Which group of pts would you want you want to avoid sulfonylurea?
sulfa allergy
They will be ineffective in type 1 dm
Waht is mechanism and site of action of sulfonylurea?
Binds to ATP dependent channel on b cells in islets of longerhans
causes an increase in intracellular Ca which results in increased fusion of insulin granulae with the cell membrane
What is primary and secondary failure of sulfonylurea?
primary-pt never achieve satisfactory response
secondary- pts become resistant
______% of sulfonylurea are protein bound
90-95% bound to albumen
where is sulfonylurea metabolized?
liver metabolism
renal excretion
Tolbutamide (orinase), Acetohexamide and chlorpropamide are examples of?
first gen sulfonylureas
Glyburide and glipizide are examples of ?
second gen sulfonylureas
What drug class does metformin belong to? HOw does it work?
biguanide
inhibits gluconeogenesis
What is the side effect of metformin?
Lactic acidosis
Metformin should be held at least _____ hours before surgery
12
Too much acarbose can induce hypoglycemia. T/F
F
IN a pt with type II diabetes, what is a strong independent predictor of cardiomyopathy?
Hgb A1C levels
What is prediabetes range of A1C?
5.7-6.4%, whcih corresponds to fasting plasma glucose test 100-125
The goal for A1C is less than _____% which is estimated average glucose of ____
7%
154
A1C measures glucose over the last ____ months
3
