pharmacodynamics Flashcards
1
Q
nitroglycerin
A
- Eg nitroglycerin is taken
§ During an angina attack to relieve pain
§ Before activities that usually cause angina
2
Q
metoprolol
A
- Metoprolol must be taken regularly to reduce occurrence of angina episodes
- Prophylactic administration
- Typical for drugs used to treat chronic diseases
- Prophylactic administration
3
Q
Potency
A
- The dose required to produce and effect
- A drug that produces its effects at lower doses is said to be more potent
-
- A drug that produces its effects at lower doses is said to be more potent
4
Q
Effectiveness
A
A drug that produces a greater maximum level of effect is said to be more effective
5
Q
- Affinity
A
- Tendency of a drug to bind to it’s target
- Depends on the existence of
§ Complementary chemical forces of attraction and
§ Complementary 3D shapes between drug and target
6
Q
fraction of target bound by drug
A
[drug]/[drug].Ka
7
Q
Ka
A
concentration of the drug at which 50% of receptors are bound
□ A measure of affinity
□ Inverse relationship - low Ka means high affinity
8
Q
Rt
A
total number of receptors
9
Q
f
A
the efficiency of coupling between receptor activation and the end effect
○ Capacity of the activated receptor in creating an effect
10
Q
- Sigmoidal dose response curve
A
○ Plot of log[agonist] vs effect
11
Q
EC50
A
- Measures agonist potency
- Concentration of a drug required to produce 50% of its maximum response
12
Q
EC50 depends on
A
○ Affinity ○ Efficacy ○ Cell dependant parameters § Density of receptors § Efficiency of coupling
13
Q
phenylephrine
A
nasal decongestant
14
Q
salbutamol
A
an asthma reliever
15
Q
Metoprolol binds
A
- Competitive antagonist
- Binds to B1 adrenocepttor and occupies the binding site of the receptor it inhibitts the binding of adrenaline to the receptor
- Blocks the binding and actions of adrenaline
