-
7/27/2019 Pharmacodynamics. MBBS Class-5
1/12
-
7/27/2019 Pharmacodynamics. MBBS Class-5
2/12
Pharmacovigilance
Actively look for adverse drug effects
Activities relating to detection, assessment, understanding and
prevention
of adverse effects or any other drug related problem
Causality assessment1. Temporal relationship
2. Previous knowledge
3. Dechallenge
4. Rechallenge
Information collected by
Regional centers to
Zonal centers to
National centers to
Uppsala monitoring center (Sweden)
Definite, probable, possible or doubtful
-
7/27/2019 Pharmacodynamics. MBBS Class-5
3/12
Quantitative estimation of a
drug
Unknown drug
-
7/27/2019 Pharmacodynamics. MBBS Class-5
4/12
Quantitative estimation of the
drug
Bio-assay[Biological method]
Chromatography, spectrophotometry,
fluorometry etc.
Radio-immunological method
Microbiological method
-
7/27/2019 Pharmacodynamics. MBBS Class-5
5/12
Quantitative estimation of a
drug
Unknown drug Known drug with
Known concentrationEg.300mg/1ml
1ml relieves head ache in 10 minutes2ml relieves head ache in 10
minutes
-
7/27/2019 Pharmacodynamics. MBBS Class-5
6/12
Bio assay
Quantitative estimation of adrug in an unknown sample by
biological method
Aspirin
Grand
mothers
bitter
decoction
Compare
Unknown
Compare
ACH
-
7/27/2019 Pharmacodynamics. MBBS Class-5
7/12
Bioassay
Acetylcholine
[Standard]
Unknown
[Suspected to
have Ach action]
Compare
Calculate concn.
Measurement of the potency[Concentration] of a drug from
the magnitude of its mainbiological effect
-
7/27/2019 Pharmacodynamics. MBBS Class-5
8/12
Bioassay uses
Acetylcholine
[Standard]
Unknown
[Suspected to
have Ach action]
Compare
Calculate concn.
1. To measure pharmacologicalactivity of new substances2. To
measure concn. Of new
substance3. ED
50
and LD50
calculations4. Standardization of drugs in
natural sources when same camnot be done by other methods
Eg.Bioassay of unknown solution isdone against the effects of
AchKnown [Ach]in frog rectus.
[Principles of pharmacology by Sharma &Sharma]
-
7/27/2019 Pharmacodynamics. MBBS Class-5
9/12
Fixed Dose Combinations
[FDCs]
Carbidopa
levodopa
The combination of two different drugs in a
single pharmaceutical formulation
Two drugs in a tablet, injection syp.etc
-
7/27/2019 Pharmacodynamics. MBBS Class-5
10/12
Fixed Dose Combinations
[FDCs]
It is not simultaneous administration of two
drugs for a disease
It should be logical [Only about 20 are WHO approved]
Advantageous
Should not be dangerous
Equal t Dose should be complimentary to plasma
concentration
-
7/27/2019 Pharmacodynamics. MBBS Class-5
11/12
Fixed Dose Combinations
[FDCs]
Advantages
Convenience of dosage-
better compliance
Synergism Reduced bacterial resistance
Minimization of side effects
Disadvantages
Independent dose
adjustments not possible
If PK characteristics do notmatch-plasma concentration
fluctuate
FDCs should not be prescribed unless:1. There is reason to
believe that pt. needs
all the drugs in the combination
2. PK parameters match
-
7/27/2019 Pharmacodynamics. MBBS Class-5
12/12
Thank you!
