pharmacology

Question 1

What is pharmacokinetics?

Answer 1

Routes of administration

Question 2

What is pharmacodynamics?

Answer 2

The effects of drugs and the mechanism of their action

Question 3

What is quantifying drug effects?

Answer 3

Efficacy and potency

Question 4

What are psychoactive (psychotropic) drugs?

Answer 4

Psychoactive drugs are drugs which after your transmission to affect a mood or behaviour

Question 5

What are psychoactive drugs effective for?

Answer 5

They may be effective in managing psychological problems

Question 6

What are psychoactive drugs? (like structure wise)

Answer 6

Psychoactive drugs are compounds that are not naturally present in the body and can be found in plants or compounds that have been synthesised in a chemical laboratory

Question 7

What are the 6 routes of drug administration?

Answer 7

1. oral (ingestion)
2. rectal
3. other mucous membranes: sublingual (under tongue) / buccal 9inside cheek) / nasal
4. transdermal
5. inhalation
6. injection: intravenous (into the vein) / intramuscular (into the muscle) / subcutaneous (into the skin)

Question 8

What are some advantages of oral administration?

Answer 8

• easy
• allows for drug to go out of the system
• limited infection risk

Question 9

What are some disadvantages of oral administration?

Answer 9

• stomach is very acidic; some drugs are broken down
• foodstuffs in gut can make absorption unpredictable (e.g. alcohol on empty /full stomach)
• some drugs irritate the stomach, induce vomiting
• blood supply from gut routed to liver, main site of drug metabolism (so called first pass effect)

Question 10

What is the first pass effect?

Answer 10

• liver metabolism breaks down active drug to metabolites for elimination
• the first-pass effect is the extent to which a drug is metabolised by the liver before reaching systemic circulation
• from the GI tract, drugs pass via the portal vein into the liver
• the result of first pass metabolism means that only a proportion of the drug reaches the circulation

Question 11

What are some advantages of rectal administration?

Answer 11

Can be used if person is vomiting or unconscious

Question 12

What are some disadvantages of rectal administration?

Answer 12

• Unpredictable rate of absorption
• Not well accepted by some

Question 13

What is a sublingual mucous membranes administration?

Answer 13

Sublingual = under the tongue
Absorbed through mucous membranes

Question 14

What is a buccal mucous membranes administration?

Answer 14

Buccal = mouth
Absorbed through lining of mouth

Question 15

What is a nasal mucous membranes administration?

Answer 15

Nasal = inhaled or snorted
Absorbed by mucous membranes in the nose

Question 16

What is an advantage of other mucous membranes administration?

Answer 16

Avoid first pass metabolism

Question 17

What is a disadvantage of other mucous membranes administration?

Answer 17

All relatively slow compared with inhalation/injections

Question 18

What are some factors that can affect diffusion of drugs across lipid membranes?

Answer 18

• lipid-soluble and small molecules drugs diffuse the best
• Un-ionsied drug molecules are more lipid soluble

Question 19

How do drugs travel in the body?

Answer 19

Drugs circulate throughout the body in plasma where they then enter tissue sites. They encounter receptors for which they have affinity to. They bind and have a pharmacological response.

Question 20

What is metabolism?

Answer 20

Metabolism converts the drug chemically into another compound which can be inert, active, or even more active

Question 21

Where does metabolism occur?

Answer 21

Mainly takes place in the liver as it contains enzymes that help metabolism, it is sometimes essential for the drug to be eliminated

Question 22

What is elimination?

Answer 22

Elimination is the process of which a drug is removed from the body

Question 23

What are the different routes of elimination?

Answer 23

Urine
Breath
Sweat
Hair

Question 24

How do drugs get eliminated through urination?

Answer 24

They are eliminated via the kidneys but is only possible for water-soluble compounds. However, fat-soluble drugs may be metabolised to make them water-soluble

Question 25

How do drugs get eliminated through breath?

Answer 25

Alcohol can get eliminated through breaths

Question 26

How do drugs get eliminated through sweat?

Answer 26

As it is often un-metabolised

Question 27

How do drugs get eliminated through hair?

Answer 27

Hair-analysis

Question 28

What is (drug) half life?

Answer 28

Half life is a measure of duration of drug action. It is the time taken for amount of drug in plasma to fall by 50%

Question 29

Why is half life relevant when considering drug manufacturing?

Answer 29

As it impacts how frequently a drug has to be taken

Question 30

What are transdermal patches?

Answer 30

The controlled release (of a drug) from a reservoir through a membrane

Question 31

What are some features of transdermal patches?

Answer 31

Long duration of action
Potential for allergic reactions to the patch or adhesives
Drug must be potent or else patches needed are too large
Sweat and moisture may life the patch

Question 32

What are some features of inhalation?

Answer 32

Gases
Aerosols
Smoke
Very fast
Gases leave and enter lung quickly
Can cause damage to lungs

Question 33

What are some features of injection (IV)?

Answer 33

Very fast
Allows accuracy in doses
Can cause clots/infection

Question 34

What are some features of intramuscular?

Answer 34

Not as fast as IV or inhalation but faster than others

Question 35

What are sone features of subcutaneous

Answer 35

Drug diffuses into area between skin and muscle
Slowest for of injection
Can only inject small volumes

Question 36

What are some factors affecting choice of route of administration?

Answer 36

• Ease of administration
• Desired onset and duration of action
• Quantity of drug to be administered
• Balance of risk versus benefits

Question 37

What is pharmacodynamics?

Answer 37

How do psychoactive drugs bring about their effect