Introduction to formulation sciences

Question 1

Drug/ active/ API

Answer 1

A substance intended to furnish pharmacological activity or to otherwise have direct effect in the diagnosis, cure mitigation, treatment or prevention of disease, or to have direct effect in restoring, correcting or modifying physiological functions

Question 2

Excipient

Answer 2

Any component, other than the active substances, present in a medicinal product or used in the manufacture of the product

Question 3

Medicine/ product

Answer 3

The complete product i.e. active(s) and excipient(s); a means of administering drugs to the body in a safe, efficient, accurate, reproducible and convenient manner

Question 4

Why formulate a medicine?

Answer 4

To improve patient compliance, stability, biopharmaceutical profile, ease of manufacture
A poor formulation can reduce or even remove activity

Question 5

Invasive methods

Answer 5

Any method of drug delivery that accesses the target via physical trauma (usually to the skin)

Question 6

Non-invasive methods

Answer 6

Any method of drug delivery that accesses the target without physical damage to tissue, usually involves crossing epithelium, harder to formulate

Question 7

Systemic delivery

Answer 7

Drug enters circulation and is transported to site of action, circulation is not usually the target, can target sites inaccessible by local application, subject to first pass hepatic metabolism, side effects

Question 8

Local delivery

Answer 8

Drug is administered close to target site, rapid onset, reduced dose, low metabolism, impermeability of epithelial tissue, transfer/spread

Question 9

Bioavailability

Answer 9

The fraction of unchanged drug reaching he systemic circulation by any route, following IV injection bioavailability of 100%, oral route has poor absorption and first pass metabolism

Question 10

For 100% bioavailability

Answer 10

Be completely released from the dosage form. be fully dissolved in the GI fluids, be stable in the GI fluids, pass through the GI barrier without being metabolised, pass through liver without being metabolised

Question 11

Bioequivalence

Answer 11

Whether two dosage forms containing an equal amount of drug are equivalent in terms of rate and extent of absorption, measured as %

Question 12

Why is compliance an issue in formulation development?

Answer 12

Pain- injections. invasive methods are not liked, convenience- complicated regimens are confusing, taste/odour- unpleasant, appearance, cost

Question 13

Excipients

Answer 13

General considerations- irritancy/toxicity, compatibility with other components and container/closure, stability, colour, flavour, smell