D1 pharmaceutical products and drug action

Question 1

medicine definition

Answer 1

medicine is something that treats, alleviates, or prevents the symptoms of disease with theraputic action

Question 2

drug definition

Answer 2

a substance that when introed to a living org, bring abt a change in biological function thru chemical action

Question 3

6 methods of administering drugs

Answer 3

• oral
• inhalation
• skin patches
• suppositories (insertion into a body orifice)
• eye or ear drops
• parenteral - by injection

Question 4

how is the long and costly process of new drug dev dealt with / what is rational drug design?

Answer 4

the process of focusing research on the identification of a suitable molecular target in the body and designing a drug to interact with it

Question 5

steps to rational drug testing 7

Answer 5

1. indentification: of a suitable molecular target to design a drug to interact w it
2. finding a lead compound – shows desired pharmaceutical activity
3. optimisation of lead compound effectveness thru synthesis and testing of analogues (chemically related compounds)
4. use of combinatorial chem to prod and test large n.o. of candidate meds (short time)
5. animal testing
6. human testing
7. determindation of theraputic index for humans + suitable dosage (via data analysis)

Question 6

what is the bioavaliability of drugs?

Answer 6

the fraction of the administered drug that reaches the blood supply

Question 7

what are the effects (physiological) of drugs? 2

Answer 7

theraputic: intended physiological effect
side effects: unintended p. e.

Question 8

explain the low oral avaliability of drugs 3

Answer 8

1. first pass effect: 20-40% reach bloodstream
2. enzymes chemically alter the drugs once in digestive system
3. aft. absorption into bloodstream in D.S. – passed to the liver, further metabolic breakdown reactions

Question 9

what are some factors? for the bioavaliability of drugs 3

Answer 9

• low oral avaliability (first pass effect)
• solubility of drug
• functional grps in drug

Question 10

What does drug action depend on

Answer 10

• drug action depends on interactions with receptors
• interactions depend on ‘chemical fit’ betw drug and receptor
  
  • typically involves various types of non-covalent bonding (ionic, hydrogen, VDW, etc)
  • receptors: typically proteins (enyzmes, chem strcuture on cell mem., DNA)

Question 11

how does solubility of drugs impact bioavaliablity

Answer 11

• water solubility: helps circulation in aq sol in blood 2
• lipid solubility: helps passge of drug thru membranes via absorption

Question 12

example for solubility of drug affecting bioavaliability

Answer 12

codeine
- bioavail 90%
- more lipid soluble than morphine
- less polar molecule

Question 13

how do functional groups in drugs affect bioavaliabiltiy

Answer 13

• pKa and pKb values determine charges carried at various pH = affects reactivity and solubility at diff parts of body
• affects acid grps more

Question 14

what does the dosage of the drug depend on

Answer 14

• bioavaliability
• possible side effects
• age
• sex
• weight
• diet
• environment
• interactions with other drugs

Question 15

what is the theraputic window

Answer 15

= the range the conc of a drug in the bllodstream should stay within
- above range = undesirable side effects
- below range = no effective effects

can be quantified as the theraputic index

Question 16

what is the theraputic index

Answer 16

the ratio of the dose that produces toxicity: the dose that produces a clinically effective response in a population

• TI in animals: 50/50

Question 17

what are the 3 markers? in the TI

Answer 17

• ED50: min effective to 50% of pop
• LD50: lethal to 50% of pop (animal trials)
• TD50: toxic to 50% of pop (human studies)

Question 18

ways to inject (parenteral)

Answer 18

• intramuscular (into muscle) eg vaccines
• intravenous (into blood, fastest) eg local anaesthetics
• subcutaneous (under skin) eg dental injections