Pharma 4

Question 1

Structure of Insulin

Answer 1

Peptide hormone composed of 2 amino acid chains (A and B) connected by disulfide bonds

Question 2

Reflects endogenous insulin secretion

Answer 2

C peptide

Question 3

Synthesis pathway of insulin

Answer 3

Preproinsulin –> proinsulin, proinsulin is then cleaved into insulin

Question 4

Insulin binds to insulin receptor also known as

Answer 4

Tyrosine kinase receptor

Question 5

Metabolism of insulin

Answer 5

When insulin is injected exogenously, the degradation profile is altered. The kidneys degrade (~60%), the liver (~30- 40%) (Reverse of endogenous)

Question 6

In renal impairment, insulin administration

Answer 6

There is a decline in exogenous insulin requirments & increased risk of hypogylcemia

Question 7

The biological action of insulin depends on

Answer 7

On he absorption from SC depot

Question 8

Therapeutic Indications of Insulin

Answer 8

1) All patients with Type 1 DM
2) Type 2 DM uncontrolled on oral agents
3) Pregnancy
4) Acute illness, surgery, infections
5) Diabetic emergencies

Question 9

Gold standard administration of insulin for T1DM

Answer 9

Pumps, continous basal infusion + user-command bolus

Question 10

Inhaled form of insulin

Answer 10

Afrezza

Question 11

Rapid acting insulin

Answer 11

Lispro, aspart, glulisine

Question 12

Short acting insulin

Answer 12

Regular (soluble), Humulin R

Question 13

Intermediate acting insulin

Answer 13

NPH (Neutral protamine hagedorn)

Question 14

Long acting insulin

Answer 14

Glargine, detemir

Question 15

Ultra-long acting insulin

Answer 15

Degludec

Question 16

Rapid acting insulin, ONSET PEAK DURATION

Answer 16

ONSET 10-15 min
PEAK 1hr
DURATION 3-4hr

Question 17

Short acting insulin, ONSET PEAK DURATION

Answer 17

ONSET 30-60min
PEAK 2-3hr
DURATION 6-8hr

Question 18

Composition of NPH

Answer 18

Insulin complexed with protamine and zinc

Question 19

Mechanism of NPH

Answer 19

Protamine delays absorption

Question 20

Appearance of NPH

Answer 20

Cloudy suspension (must be mixed)

Question 21

Disadvantages of NPH

Answer 21

Pronounced peak & Risk of nocturnal hypoglycemia

Question 22

NPH, ONSET PEAK DURTION

Answer 22

Onset: 2-4 hrs
Peak: 4-10 hrs
Duration: 12-18 hrs

Question 23

Use of NPH

Answer 23

Usually given twice daily (BD) for basal coverage.

Question 24

Glargine mechanism & duration

Answer 24

Precipitates at neutral body pH forming crystals that slowly release the insulin

~24 hrs

Question 25

Detemir mechanism & duration

Answer 25

Binds to albumin (fatty acid chain) 16-24hrs

Question 26

Degludecc mechanism & duration

Answer 26

Forms multi-hexamers >40hrs

Question 27

Common premixed (biphasic) insulins

Answer 27

1) 70/30: 70% NPH, 30% Regular 2) Humalog Mix 75/25: 75% NPL, 25% Lispro

Question 28

Disadvantages of Premixed (Biphasic) Insulins

Answer 28

▪ Fixed ratio, Cannot titrate the meal dose without changing the basal dose ▪ High risk of hypoglycemia if meals are skipped

Question 29

Twice Daily (Split-Mixed) regimen

Answer 29

NPH + Regular given before Breakfast and Dinner

Question 30

Twice Daily (Split-Mixed) regimen mechanism

Answer 30

o Morning NPH covers Lunch. o Morning Reg covers Breakfast. o Evening NPH covers night.

Question 31

Systemic side effects of insulin

Answer 31

▪ Hypoglycemia (most important) ▪ Hypokalemia (rare) ▪ Weight gain: due to anabolic effects of insulin ▪ Insulin resistance ▪ Hypersensitivity reactions ▪ Dry cough & bronchospasm. (Afrezza)

Question 32

Local side effects of insulin

Answer 32

Lipodystrophy: (atrophy or hypertrophy) of s.c. tissue after repeated injections