Insulins

Question 1

How can insulin be administrated?

Answer 1

1. Subcutaneous: home setting (most insulins)
2. IV: emergencies, hospital setting (only for regular insulin, short-acting)
3. IM: cannot
4. Nasal: inhale to lungs => only avail in rapid onset medicines (cuz lungs r very vascularised) (new tech)

Question 2

What is the function of basal insulin?

Answer 2

• for body to suppress hepatic glucose production overnight & btw meals

Question 3

What is the function of prandial insulin?

Answer 3

• body needs the insulin to dispose glucose after meals

Question 4

What are the factors influencing the PK of insulin?

Answer 4

Pharmacokinetics refers to the movement of drugs through the body, aka what the body does to the drugs.

1. Site of injection
2. Depth of injection (generally, deeper=> faster absorption)
3. Larger volumes (slows rate of ab)
4. Exercise before injection (increases rate of ab)
5. Application of heat/massaging at injection site (increases rate of ab)

Question 5

Which sites of injection leads to higher rate of absorption of insulin?

Answer 5

Abdomen=> faster rate of absorption + more reproducible than arms/buttocks/thighs
- due to diff in blood flow

Question 6

How does the depth of injection affect the rate of absorption of insulin?

Answer 6

Too deep=> delivers into muscles, greater vascularisation than in subcutaneous tissue => faster absorption

Too shallow=> superficial injection in derma => slow & incomplete absorption

• conflict w predicted onset/peak time/duration of action

Question 7

What are the 2 main needs to be satisfied via insulin therapy?

Answer 7

1. Basal insulin
2. Prandial insulin

Question 8

Name the 3 rapid-acting insulin analogues

Answer 8

1. Lispro
2. Aspart
3. Glusinine

Question 9

Which type of insulin can be injected intravenously?

Answer 9

Regular insulin (short-acting insulin)

Question 10

What are the 2 types of long-acting insulins?

Answer 10

1. Glargine
2. Detemir

Question 11

What are long-acting insulin analogues useful for?

Answer 11

• takes care of basal insulin needs

Question 12

Why can’t long-acting insulins be mixed in the same syringe with other insulins?

Answer 12

• it’ll change how the insulins work
• prolly cuz of the association into hexamers blahblah (go read the detemir part) & cuz of incompatible pH (for glargine)

Question 13

Name an ultra long-acting insulin and what is its duration of action?

Answer 13

Degludec, DOA>24h

Question 14

Name an advantage and disadvantage of Degludec:

Answer 14

Advantage: it can be mixed in a syringe (unlike long-acting insulins, glargine & detemir)

Disadvantage: inability to tweak day to day levels due as it is ultra long-acting

Question 15

Which insulin drug comes w the highest risk of hypoglycemia?

Answer 15

Intermediate-acting: Neutral Protamine Hagedorn (NPH)

Due to:
- high intra & inter patient variation
- long peak

Question 16

Rank the different types of insulin drugs in decreasing risk of hypoglycemia.

Answer 16

3. Intermediate > 2. Short > 1. Rapid > 4. Long > 5. Ultra-Long

Why?
Intermediate has highest risk cuz of long peak + high intra & inter patient variation
Short has higher risk than Rapid cuz the longer the DOA, the greater the risk of **hypoglycemia **
BUT
For long n ultra-long, each has lower intra-px variation n PD variation, thus, lower risk of hypoglycemia

Question 17

Name the common adverse effects of insulin drugs.

Answer 17

1. Hypoglycemia
2. Lipodystrophy
   - lipoatrophy &/or lipohypertrophy

Question 18

What are the 2 types of lipodystrophy and what causes them?

Answer 18

1. Lipoatrophy
   - loss of fat at site of injection
   - occured in past due to usage of animal insulin, when recombinant insulin didnt exist
2. Lipohypertrophy
   - accumulation of fat, due to repeated injection at same site
   - due to lipogenic action of insulin
   - that’s why site of injection needs to be rotated to prevent lipohypertrophy at only one site.

Question 19

Compare the duration of action and adverse effects of rapid-acting vs short-acting insulins:

Answer 19

DOA: rapid<short
Thus, short has a greater risk of hypoglycemai than rapid

Question 20

Which insulin has a unique appearance from the rest?

Answer 20

Intermediate acting- Neutral Protamine Hagedorn(NPH) insulin
- cloudy appearance
- the rest of the insulins are clear