Updated: 9/6/2020

Pharmacodynamics

0%
Topic
Review Topic
0
0
N/A
N/A
Questions
1 1
0
0
0%
0%
Videos
1 1
Topic
Competitive vs. noncompetitive antagonist
  • Competitive
  • shifts agonist curve to the right
    • characteristics
      • resembles substrate [S]
      • blocks active site and can be overcome by ↑ [S]
      • ↓ potency, ↑ Km, and Vmax is unchanged
  • Noncompetitive antagonist 
    • shifts agonist curve downward
    • characteristics
      • does not resemble [S]
      • does not block active site, therefore no ↑ [S] can overcome effect
      • ↓ efficacy and potency, ↓ Vmax, and Km is unchanged
      • ↑ EC50 of agonist (half maximally effective concentration for producing a given effect)
Agonist vs. partial agonist
  • Agonist
    • acts on the receptor and triggers a full response (100% effect)
  • Partial agonist
    • acts on the same receptor as the full agonist
    • ↓ efficacy, independent of dose
    • may be more potent, less potent, or equally potent
      • potency is an independent factor
    • can compete with full agonist to inhibit some of the response of the full agonist
Synergism & Potentiation
  • Synergism
    • the combined action of two drugs is greater than the activity of either alone (in total)
      • for example: monobactams and aminoglycosides
  • Potentiation
    • drug A is required for the full effect of drug B to occur, but drug A itself does not have much of an effect (unlike synergism)
Topic Rating

Please rate topic.

Average 4.3 of 7 Ratings

 

Questions (1)
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
VIDEOS (1)
Topic COMMENTS (14)
Private Note