W19 Drugs and therapeutics

Question 1

What is a drug?

Answer 1

Chemical with a selective therapeutic action

Question 2

What is Pharmacodynamics (PD) Vs Pharmacokinetics (PK)?

Answer 2

Pharmacokinetics- What the drug does to the boy,
- Drug action and mechanisms
Pharmacokinetics- What the body does to the drug
- Barriers (ADME)

Question 2

What is Pharmacodynamics (PD) Vs Pharmacokinetics (PK)?

Answer 2

Pharmacokinetics- What the drug does to the boy,
- Drug action and mechanisms
Pharmacokinetics- What the body does to the drug
- Barriers (ADME)

Question 3

What is the role of Adrenergic receptor- ‘beta’ (β-1)?

Answer 3

• Increases heart rate
• Increasing cardiac muscle’s force of contraction

Question 4

What is the role of Adrenergic receptor- ‘beta’ (β-2)?

Answer 4

• Relaxes the airway
• Dilatate smooth muscles

Question 5

What is specificity?

Answer 5

Chemical: “right target binding site”
Target binding sites (receptors & its subtypes) provides the selectivity for the specific binding of drugs/ligands (LOCK & KEY system)

Question 6

Example of a competitive inhibitor:

Answer 6

Neostigmine is a competitive inhibitor with Acetylcholine which competes to bind with the acetylcholine esterase.
Can be reversible and irreversible

Question 7

What is the function of a non- competitive inhibitor?
Example?

Answer 7

Drugs bind at an allosteric/ different site

COX- Enzyme
Arachidonic acid binds to COX
Aspirin- Non-competitive Inhibitor

Aspirin will compete with Arachidonic acid to bind with COX
Can be irreversible and reversible

Question 8

What are some examples of drugs used as enzyme inhibitors?

Answer 8

Intracellular breakdown: Phosphodiesterase (enzyme) and Sildenafil used
Neurotransmitter degradation- Acetylcholine esterase and Neostigmine
Messenger synthesis- Cyclo-oxygenase and Ibuprofen (reversible) and Aspirin (irreversible)

Question 9

Example of a drug targeting voltage-gated ion channels
What is it used as?

Answer 9

Lidocaine blocks Sodium channel
Used as a local anaesthetic

Question 10

Example of drugs targeting transporters:

Answer 10

Noradrenaline

Question 11

Example of drugs targeting receptors:

Answer 11

Messengers (endogenous ligands)
E.g. hormone, peptides, cytokines, neurotransmitters

Key types of receptors
* Nuclear receptors
* Ligand gated ion channel
* Catalytic receptors
* G-protein coupled receptors

proteins which respond to a endogenous messenger by initiating a signal

Question 12

General characteristics of receptors

Answer 12

Selectivity of ligands-Molecular switch
Amplification of signals