7/21/2019 Antagonisme Farmakodinamika New

1/16

AGONIS-ANTAGONIS

FARMAKODINAMIKA

Fifteen Aprila F., S. Farm, Apt

7/21/2019 Antagonisme Farmakodinamika New

2/16

Pengertian AGONIS?

Agonis PARSIAL

Pengertian ANTAGONIS

Antagonis FISIOLOGIK

Antagonis RESEPTOR

Antagonis KOMPETITIF

Antagonis NON KOMPETITIF

7/21/2019 Antagonisme Farmakodinamika New

3/16

Receptor

Drugs

Some Effect

A Cell

7/21/2019 Antagonisme Farmakodinamika New

4/16

Obat yg bila menduduki reseptormenimbulkan ef farmakologi scr intrinsik.

7/21/2019 Antagonisme Farmakodinamika New

5/16

Agonis lemah

Ar/ agonis yg memp aktvitas intrinsik atau

efektivitas yg rendah shg ef maksimalnya

lemah.Disebut jgantagonis parsial

Obat ini mengurangi ef maksimal yg

ditimbulkan agonis penuh.

Ex : Nalorfin (antagonis/agonis parsial u/resptor morfin)

AGONIS PARSIAL

7/21/2019 Antagonisme Farmakodinamika New

6/16

menurunkan aktivitas intrinsik

menurunkan afinitas

7/21/2019 Antagonisme Farmakodinamika New

7/16

Kurva X : Efek maksimal yg dihslkan oleh A

Kurva Y : Efek maksimal yg dihslkan oleh A + Agonis

dg dosis yg menimbulkan efek maksimal < Emax (A)

Kurva Z : Efek maksimal yg dihslkan oleh A + Agonis

dg dosis yg menimbulkan efek maksimal > Emax (A)

7/21/2019 Antagonisme Farmakodinamika New

8/16

Drugs A

Antagonist

Dude, youre

in my way!

7/21/2019 Antagonisme Farmakodinamika New

9/16

Obat yg menduduki reseptor yg

sama, tp scr intrinsik tdk mampu

menimbulkan efek farmakologi.

So: antagonis akan menghalangi ik

reseptor dg agonis shg kerja agonis

terhambat.

7/21/2019 Antagonisme Farmakodinamika New

10/16

7/21/2019 Antagonisme Farmakodinamika New

11/16

ANTAGONIS FISIOLOGIKTjd pd organ yg sama, pd sistem reseptoryg berbeda.Ex : efek bronkokonstriksi histamin pd bronkus dan

bronkodilatasi adrenalin (adrenoreseptor )pd bronkus.

ANTAGONIS PD RESEPTORTjd mll sistem reseptor yg sama.

Ar/ antagonis mengikat reseptor d tmp ikagonis (receptor/active site).Ex : efek histamin pd rx alergi dpt diatasi dg pemberianantihistamin yg bekerja pd reseptor yg sama)

7/21/2019 Antagonisme Farmakodinamika New

12/16

Antagonis KOMPETITIF

antagonis berik dg receptor site scr

reversibel shg dpt digeser o/ agonis kdr

tinggi. (Ex : -bloker & antihistamin)

Antagonis NON KOMPETITIF

penghambatan ef agonis tdk dpt diatasi dg

me kdr agonis (sifatnya irreversibel),akibatnya ef mak akan berkrg, ttp afinitas

agonis thd reseptornya tdk berubah.

(Ex : fenoksibenzamid pd reseptor adrenergik)

7/21/2019 Antagonisme Farmakodinamika New

13/16

Afinitas agonis thd

reseptor menurun

Kurva bergeser sejajar

ke kanan

Ef maksimal yg dicapai

agonis sama

7/21/2019 Antagonisme Farmakodinamika New

14/16

Ef maksimal yg dicapai agonis berkrg

Afinitas agonis thd reseptor tdk

berubah.

7/21/2019 Antagonisme Farmakodinamika New

15/16

Biol

ogicalEffect

Drug Concentration

Effective Dose

Drug Alone

Drug +Non-competitive

AntagonistDrug +

PartialAgonist

Drug +Competitive

Antagonist

7/21/2019 Antagonisme Farmakodinamika New

16/16

http://images.google.co.id/imgres?imgurl=http://www.cksinfo.com/clipart/holidays/thankyou-note.png&imgrefurl=http://www.cksinfo.com/holidays/page2.html&usg=__d-jrflK7FGZw8wmkUh38VKEE9n0=&h=282&w=360&sz=10&hl=id&start=39&um=1&tbnid=BJ9qCWmKZv1g4M:&tbnh=95&tbnw=121&prev=/images%3Fq%3Dthank%2Byou%2Bclipart%26ndsp%3D20%26hl%3Did%26sa%3DN%26start%3D20%26um%3D1