Pharmacologicsl Factors Affecting Drug Bioavailability- Dose Calculations

Question 0

Principle stages in tablet formation

Answer 0

Drug+excipient-> mixing -> add granulation liquid and binder-> wet granulation-> drying-> lubricant and extragranular disintegratation-> mixing-> compression-> coating

Question 1

Typical ingredients

Answer 1

Therapeutic agent
Diluent-> main tablet bulk-> lactose, sorbitol
Compression aid-> aids tablet formation-> cellulose
Binder-> binds powders into granules
Glidant-> powder flows into tablet machine
Lubricant-> tablet ejection from dye
Disintegrant-> swells/disrupts tablet on contact with body fluids
Coatings-> organoleptic modification-> enteric/sustained release

Question 2

Bioequivilance

Answer 2

Identical rate and extent of absorption 
Assessed by 
tMax-> time to peak plasma level
lMax-> peak plasma level
And bioavailability

Question 3

Acid labile formulations

Answer 3

Enteric coated tablets 
Non cellulose derivative polymers used 
Methacyclic acid components-> acid functional group
-> pKa 4.66
Omeprazole

Question 4

Transdermal formulations

Answer 4

Patches
Sustained drug delivery-> longer duration of action
Enhancers such as ethanol improve skin penetration
GTA for angina
Nicotine

Question 5

Subcutaneous formulations

Answer 5

Control of absorption of insulin from site of injection achieved by differences in physical state of insulin
-> in zine or protein content
-> in pH of suspending buffer
Short acting-> soluble-> rapid onset,short duration
Intermediate-> suspension with procaine-> twice daily
Long acting-> large crystals, high zinc content

Question 6

I.M formulations

Answer 6

Absorption by use of thick oils that slow diffusion rate

Norethisterine enatate

Question 7

Percentage solution drug expression

Answer 7

Means grams per 100ml of solution
100%-> 100g per 100ml
1% -> 10mg/ml

Question 8

Ratios

Answer 8

1: 1000-> 1mg/ml
1: 20,000-> 5mg/ml

Question 9

Units

Answer 9

A measure of biological activity

Specific to each drug