DM Facts and Insulin

Question 1

Differentiate TID from T2D.

Answer 1

T!D: inability to produce insulin
T2D: Down regulation of insulin receptors and desensitization of insulin receptors s/p poor diet, lack of exercise, and obesity.

Question 2

What is recombinant insulin?

Answer 2

Made from human proteins in a lab.

Question 3

Other than recombinant, what are two other sources of insulin and why are they not commonly used?

Answer 3

Bovine and porcine (cow and pig) - higher risk of allergic reactions and recombinant insulin is more rapidly absorbed.

Question 4

How can recombinant insulin be modified in a lab?

Answer 4

Analogues added to the insulin molecule to modify onset and/or duration of action.

Question 5

What are the three primary physiologic effects of insulin?

Answer 5

1. activate glucokinase and glucose phosphatase
2. convert glucose to glycogen
3. enhance amino acid and K entry into cells

Question 6

What is the general rule for dosing insulin and where do you start for a new patient?

Answer 6

1 unit of insulin used per kg of body weight. Start a new patient at 80% of daily use then titrate PRN.

Question 7

What is the main drug that induces hyperglycemia? List some others that cause hyperglycemia.

Answer 7

1 - steroids. Others - glucagon, epi, thyroid hormones, oral contraceptives, HCTZ/diuretics (mild increase)

Question 8

Why is insulin not administered PO?

Answer 8

Stomach acid will denature the proteins that make up insulin.

Question 9

What are the three factors on which insulin formations may vary from one another?

Answer 9

1. Strength (concentration)
2. Source (human or animal)
3. Formulation (immediate, short, intermediate, long)

Question 10

List and describe the insulins in each category of formulation.

Answer 10

Immediate: Lispro - closest to regular insulin
Short: regular insulin - quick on, quick off
Intermediate: NPH - administered BID
Long: Detemir and Glargine - administered QD

Question 11

Describe the initial insulin dosing regimen for a new T1D patient.

Answer 11

Start with conventional insulin BID - 2/3 dose in the morning and 1/3 at bedtime - with q6h BGL checks

Question 12

What does it mean for insulin to be “70/30”?

Answer 12

70% long acting agent (NPH) and 30% short acting agent (Lispro) in one vial. The first number is always indicative of the longer acting insulin’s percentage

Question 13

What is conventional insulin?

Answer 13

2 injections of 70/30 insulin - 2/3 of total daily dose given in the AM and 1/3 given at bedtime.

Question 14

Under what age is insulin typically required for DM?

Answer 14

Under 30 years of age

Question 15

List the sites of insulin injection from fastest rate of absorption to slowest.

Answer 15

Fast: abdomen and flank
Medium: deltoid
Slow: gluts and quadriceps

Question 16

Why is it important for patients on insulin to alternate injection sites?

Answer 16

Repeated injections of insulin cause lipodystrophy (fat depletion)

Question 17

Which types of insulin can and cannot be mixed in the same vial.

Answer 17

Short acting insulins may be mixed together. Long acting insulins cannot be mixed.

Question 18

What type of insulin is administered in an IV gtt and why?

Answer 18

Short acting (regular and lispro) bc long acting insulins are suspensions that will precipitate in IV fluid. Also nonsensical to use anything other than short acting insulin for patients requiring IV admin.

Question 19

What is the standard strength of insulin and what size syringe should always be used for injection?

Answer 19

100 units/ml –> use 1ml syringe s/p insulin being very concentrated.

Question 20

When must insulin be refrigerated?

Answer 20

When it will not be used within 30 days.

Question 21

Why is an insulin syringe rolled rather than shaken to mix the suspension?

Answer 21

Shaking denatures the proteins causing foam formation.

Question 22

What is the result of infections on BGL

Answer 22

BGL rises and can cause hyperglycemia

Question 23

Why are DM patients that become pregnant typically switched from PO meds to insulin?

Answer 23

Most PO meds cross the blood-placenta barrier and insulin does not.

Question 24

What effect does beta blocker use have on DM patients?

Answer 24

Beta blockers mask the S/S of hypoglycemia

Question 25

In addition to oral hyperglycemics, what other meds to DM patients usually take?

Answer 25

ACE Inhibitors and statins