IC10 Pharm Tech II Flashcards

1
Q

What class of drug is midazolam (Brand name: nayzilam) ?

A

Benzodiazepine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the MOA of nayzilam/midazolam?

(Think of the MOA of benzodiazepines)

A

Increase GABA activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is midazolam used for?

A

A nasal spray medicine used for the short-term treatment of seizure clusters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The dosing regimen of midazolam is:

a. 1 dose/spray w onset of symptoms
b. Extra dose if symptoms persist after 10 mins
c. No more than 2 doses per episode

d. Max dose:
- No more than once every 3 days
- No more than 5 times per month

Why do we limit dosing so strictly with the use of midazolam?

A

There can be a build-up of tolerance. This can result in a greater dose needed to achieve the same level efficacy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 5 criteria in the Lipinski’s rule?

A

MW: <500Da
LogP: <5
H bond donors: ≤ 5
H bond acceptors: ≤ 10
Unionised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do delivery systems help drugs in intranasal delivery?

A
  1. Make drugs physically manageable
  2. Improve solubility
  3. Improve absorption
  4. Protect drug from degradation & excretion
  5. Improve drug retention
  6. Reduce side effects (through targeting)
  7. Increasing dosing
  8. Reduce frequency of administration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Paracellular transport:

a. Are 10 micron particles likely or unlike to undergo paracellular transport?

b. Is paracellular transport a passive or active process?

A

Paracellular transport:

  1. Is unlikely for 10 micron particles
  2. Is a passive process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 5 types of parenteral delivery?

A
  1. Intramuscular
  2. Subcutaneous
  3. Intravenous
  4. Intradermal
  5. Intrathecal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the angles to administer for all 5 parenteral delivery methods?

  1. Intramuscular
  2. Subcutaneous
  3. Intravenous
  4. Intradermal
  5. Intrathecal
A
  1. Intramuscular - 90°
  2. Subcutaneous - 45°
  3. Intravenous - 25°
  4. Intradermal - 10-15°
  5. Intrathecal - 5-15°
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which parenteral delivery method is used to administer drug to the brain?

A

The intrathecal method.

Intrathecal delivers the drug into the cerebrospinal fluid, which then directly flows into the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the composition of the cerebrospinal fluid?

A

99% - water
1% - protein, ions, neurotransmitters & glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the total volume of cerebrospinal fluid & how much is produced per day?

A

Total volume: 150mL
Vol produced per day: 430-530mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the 2 main benefits of using intrathecal as the your parenteral delivery method?

A

Intrathecal delivery is able to bypass the blood brain barrier whereas other parenteral delivery method is not able to.

Intrathecal has a smaller volume of distribution - 150mL CSF fluid

Other parenteral delivery method has to distribute across the entire body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 5 main advantages of parenteral delivery over other methods of delivery (e.g oral)?

A
  1. Bypass hepatic 1st pass metabolism
  2. Ability to control dosage
  3. Direct access to the brain - intrathecal
  4. Sustained release - e.g. IM depots
  5. Ideal for non-compliant, unconscious or dysphagic patients.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the percentage of small molecules blocked by the blood brain barrier?

A

98% of small drug molecules are blocked by the blood brain barrier.

This is due to the BBB’s tight junctions and transcellular transport.

Transcellular transport - contains efflux transporters, carrier mediated transporters, receptor-mediated transporters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The blood brain barrier has 3 types of efflux transporters.

List out the 3 efflux transporters.

A
  1. P-glycoprotein (P-gp)
  2. Breast cancer resistance protein (BCRP)
  3. Multi-drug resistance proteins (MRP)

These efflux transporters prevent drug from entering the brain.

17
Q

We learnt the Lipinski’s rule for intranasal delivery.

However, the Lipinski’s rule has been modified for CNS intrathecal delivery.

List out the 5 criteria for the Modified Lipinski’s rule.

A

Molecular weight: <450 Da
H bond donors: <3
H bond acceptors: <7
LogP: 1-3
Unionised

18
Q

What are 5 common excipients used in solutions for injections?

A
  1. Diluent
  2. Buffer salts
  3. Tonicity adjusters
  4. Preservatives - minimal for intrathecal
  5. Stabilisers/co-solvents
19
Q

What is the ideal characteristics of parenteral delivery?
1. Recommended pH of drug formulation
2. Tonicity level
3. Particle size

A

Ideal pH of parenteral delivery is 7.4, but a wide range is tolerated.
IM - pH 3 to 11
SC - pH 3 to 6

Tonicity - 280 to 290 mOsm/L for large volume parenteral. We want to ensure that the drug delivered is isotonic.

Particle size - no visible particles

20
Q

What are types of packing & storage for parenteral delivery?

A
  1. Glass ampoule - tiny glass bottles with score line for breakage
  2. Glass vial w rubber stopper
  3. Pre-filled syringes
21
Q

If a parenteral formulation is not able to be isotonic, which is preferred, hypotonic or hypertonic?

A

Hypertonic is preferred.

Hypotonic can cause cells to rupture, permanently losing their function.

Hypertonic can cause cells to become flaccid, but the cells can regain their function when rehydrated.