Lecture 12a

Question 1

Methylphenidate vs Metadate

Answer 1

Methylphenidate has a fast dissolution rate

Methylphenidate has a lower total release

Question 2

Solubility 1

Answer 2

• should be considered along with its dose
• even poorly soluble drugs can completely dissolve under the right conditions with a small dose
• Dose Solubility Volume is more relevant than solubility alone

Question 3

Solubility 2

Answer 3

• a drug is “low solubility” if more than 250 mL of water is required to dissolve the largest dose at any pH at 37 degrees C
• 250 mL is chosen because it is the assumed minimum initial gastric volume available

Question 4

Bioavailability

Answer 4

• dependent upon having the drug in solution, but also the drug’s permeability
• many drugs and substances has a permeability to a fraction absorbed of 90% or better

Question 5

Polymers for Non Enteric Film-Coating

Answer 5

Cellulose coatings

• HPMC
• Methylhydroxyethylcellulose
• ethylcellulose
• HPC

Question 6

Enteric Polymers

Answer 6

• release drug in small intestine but not the stomach
• OMEPRAZOLE (totally dependent on enteric coating)
• CAP
• HPMCP
• PVAP

Question 7

Matrix Tablet

Answer 7

• drug embedded in polymer matrix

Erosion: both polymers go away and release drug
Diffusion: drug diffuses out of the polymer (intact)

Question 8

Osmotic Pump in Concerta

Answer 8

Contains:
- osmotic core
- semipermeable membrane
- delivery orifice (drug released out of) by laser hole delivery

Water can come in, drug stays within

Drug comes out slowly all day long

Question 9

GI Transit Time of OROS

Answer 9

Stomach (fasted)
- average time is 30 minutes

Stomach (fed)
- average time is 2-3 hours

Small Intestine
- average time is 3 hours

Colon
- average time is 32 hours

Question 10

Concerta vs Metadate

Answer 10

• advertising about school time frames for drugs

Question 11

Immediate vs Delayed vs Extended

Answer 11

Immediate: Fast onset of the drug and releases fast –> out of blood in short amount of time

Delayed: Slow and delayed onset of the drug –> out of blood after spiking in short amount of time

Extended: gradual release of the drug over time with a smaller intensity of the drug

Question 12

OROS vs IR

Answer 12

• IR contained many peaks and valleys in the release of the drug in the blood plasma
• OROS is a constant release of the drug and a constant amount of drug in blood plasma over time