Biopharmaceutics and pharmacokinetics are concerned with how the body affects a drug. Biopharmaceutics studies how drug formulation influences therapeutic effects. Pharmacokinetics studies the absorption, distribution, metabolism and elimination of drugs over time and their relationship to effects. Together they allow rational drug design to optimize delivery and maintain therapeutic drug concentrations. Pharmacodynamics complements pharmacokinetics by studying the biochemical and physiological effects of drugs and their mechanisms of action.

1. Biopharmaceutics
&
Pharmacokinetics
Introduction

2. Biopharmaceutics:-
* Bio – life
* Pharmaceutics
– general area of study concerned with
the formulation, manufacture, stability
and effectiveness of pharmaceutical
dosage forms.

3. Core Areas of Pharmacy
1. Drug Design:-
Involves designing and synthesizing compounds to find a specific chemical
substances that will cure, manage or prevent diseases: Cancer, AIDS, Ebola
2. Drug Formulation:-
Mix various chemical compounds with the drug to create Tablet ,Suspension,
Emulsion, Injection.
(These chemicals should not react with drug)
3. Drug Dispensing:-
Give the right drug to the right patient in right dose and duration with
sufficient counseling
(Biopharmaceutics has application on all three above)
4. Others (manufacturing, marketing and regulatory issues)

4. Drug?
• Drug is a chemical substance used in the treatment, cure, prevention, or diagnosis
of disease or used to otherwise enhance physical or mental “well-being”.
“Specific organic compound which has therapeutic effect”

5. Biopharmaceutics Bio + Pharmaceutics
Understanding “Bio” in Biopharmaceutics:-
Paracetamol
Anti-inflamatory
•How to consume?
•How much to consume?
•What happens if instead of 3 tablets, we take 6 or 9 tablets of Paracetamol on hopes of
better or quicker recovery?
•How about we share a single tablet between two person?
•How much is too much or too less?
Understanding Pharmaceutics:-
• Pharmaceutics is science dealing with drug formulation
• Drug formulation means process of mixing drug with other chemicals to prepare a
physical form which facilitates convenient dosing(intake) for patients
• That physical forms are Tablets, suspension, emulsion, syrup or solutions. This is also
called oral dosing.

6. Biopharmaceutics is defined as the study of factors influencing the rate and amount of
drug that reaches the systemic circulation and the use of this information to optimize the
pharmacological or therapeutic activity (efficacy) of the drug products.
“Study of the influence of formulation on therapeutic activity of a drug product”.
Rationale:-
The development of biopharmaceutical principles allowed for the rational design of drug
products, which would enhance the delivery of active drug, and optimize the therapeutic
efficacy of the drug in the patient.
Aim:-
The aim of Biopharmaceutics is to adjust the delivery of drug to the general circulation in
such a manner as to provide optimal therapeutic activity for the patient.

7. Concept of drug therapy :-
First thing to do…..
Understand that ALL drugs must be present in blood/plasma to show therapeutic
effect
• Depending on drug concentration in plasma either of three results: no effect,
therapeutic effect, side/toxic effect of drug.
Effect of Increasing blood concentration on drug therapeutic effect
• This information is the first thing obtained during drug Human trials. Thus we
already know how much drug must be present in blood for therapeutic effect to
occur.
• When we take a single dose, our interest is to provide just enough drug to keep the
drug concentration within the therapeutic region.

8. Secondly, think about the time course of a drug:-
The drug concentration in plasma varies continuously after we take a single dose.
We cannot keep on maintaining drug concentration in the therapeutic region by only a
single dose. Thus we need to give another dose
But what factors are making drug concentration to decrease and How to know when to
give another dose?????

9. From above graph following phenomenon has to be considered
– Absorption – drug enters blood circulation by process of diffusion
– Distribution – drug is distributed from blood to fat, muscle, organs
– Metabolism – drug structure is enzymatically altered
– Elimination – Drug is thrown out from body
• Study of these 4 parameters is called pharmacokinetics
Pharmacokinetics defined as the study of time course (kinetics) of drug
absorption, distribution, metabolism and elimination (KADME) and their
relationship with its therapeutic and toxic effects of the drug.
“WHAT THE BODY DOES TO THE DRUG”
The use of pharmacokinetic principles in optimizing the drug dosage to suit
individual patient needs and achieving maximum therapeutic utility is called as
clinical pharmacokinetics.
Population pharmacokinetics:-The study of pharmacokinetic differences of drugs
in various population groups.
Toxicological pharmacokinetics / Toxic kinetics:- is the application of
pharmacokinetic principles to the design, conduct, and interpretation of drug
safety evaluation studies and in validating dose-related exposure in animals.

10. Pharmacokinetic (ADME )Processes
The process of movement of drug from its site of administration to systemic
circulation is called as absorption.
Other processes that play a role in the therapeutic activity of a drug are drug
distribution & elimination. Together ,they are known as drug disposition.
The processes that tend to lower the plasma concentration of drug is said to be drug
disposition.
The movement of drug between one compartment and the other (generally blood
and the extra vascular tissues) is referred to as drug distribution.
Elimination is defined as the process that tends to remove the drug from the body
and terminate its action.
Elimination occurs by two processes—
biotransformation (metabolism), which usually inactivates the drug, and
excretion which is responsible for the exit of drug/metabolites from the body.

12. The fundamental characteristic of pharmacokinetic study is drug removal from the
body. This can be calculated by “Analyzing relation between peak plasma levels of drug
(Cs) with time factor”.
Pharmacokinetics cannot be studied alone without a similar equal response that is
produced by the body upon receiving the drug, called as PHARMACODYNAMICS.
Pharmacodynamics: - The study deals with the,
Biochemical and physiological effects of the drug.
Mechanism of action.
It is characterized by the concentration of drug at the site of action & relation to
the magnitude of effects observed.
“WHAT THE DRUG DOES TO THE BODY”

14. How Do Drugs Interact With Biological Systems?

15. SCHEMATIC ILLUSTRATION OF RELATIONSHIP BETWEEN PHARMACOKINETIC AND PHARMACODYNAMIC PHASES

16. Schematic representation of the processes involved in drug therapeutics (Drug administration&
Drug therapy):-