Intro to Drugs & Pharmacy

Question 1

What are the challenges in drug delivery?

Answer 1

1. Attaining accuracy and precision of low dose drugs,
2. Stabilization and delivery of large molecules (peptides and proteins)
3. Overcoming the practical problem where large dose drugs lack the properties to be formed directly into tablets
4. Delivery of poorly soluble and/or poor permeable drugs
5. Design of customized drug delivery

Question 2

What is local/topical therapy?

Answer 2

Therapeutic agent applied directly to site of action

Question 3

What is systemic therapy?

Answer 3

Drug administered systemically into blood to be transported to the site of action

Question 4

Mechanism of drug absorption

Answer 4

1. Paracellular - through gaps/pores between cells, small molecules
2. Transcellular - through cells -> biological membranes, main mechanism is diffusion (molecules must have lipid solubility, unionised form), active transport, facilitated diffusion, pinocytosis, endocytosis molecules like some peptides, particles

Question 5

If absorption is rate limiting, bioavailability no longer governed by physicochemical properties and formulation variables. True/False?

Answer 5

True

Question 6

What is preformulation`

Answer 6

Characterization of a drug’s physical, chemical and mechanical properties in order to choose what other ingredients should be used in the preparation

Question 7

What is formulation

Answer 7

Process in which the API (drug) and excipients are combined to produce a final medicinal product

Question 8

Dosage form functions?

Answer 8

Drug delivery system -> get drug to its site of action

Question 9

Factors to consider when designing dosage form

Answer 9

• Rate of delivery
• Site of release
• Target delivery to specific cells/receptors