This 6-page document discusses the relationship between biopharmaceutics and dosage form design. It begins by defining biopharmaceutics as the study of factors that influence the rate and amount of drug reaching systemic circulation in order to optimize drug efficacy. These factors include drug product design, stability, manufacture, release from the product, dissolution rate, and delivery to the site of action. It then discusses key concepts like absorption, distribution, elimination, and metabolism that influence this relationship. The document explains how solubility, permeability, stability, and pharmacokinetics impact drug bioavailability and effectiveness. It also notes how intended use, patient acceptability, and safety must be considered in dosage form design. In general, liquid dosage forms are more readily

1. Page 1 of 6
MAWLANA BHASHANI SCIENCE AND TECHNOLOGY UNIVERSITY
Santosh,Tangail-1902, Bangladesh
DEPARTMENT OF PHARMACY
ASSIGNMENT NO : 01
Course Code : PHA-3207
Course title : Biopharmaceutics & Pharmacokinetics-I
Assignment title : Relation between biopharmaceutics and
Dosage form design.
Submission date: 11/02/2023
Submitted by :
Md Jahangir Alam
Student id : PHA-19001
Session : 2018-19
Submitted to:
Dr. Mizanur Rahman Moghal
Professor
Department Of Pharmacy
Mawlana Bhashani Science
And Technology University.

2. Page 2 of 6
Biopharmaceutics
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 therapeutic efficacy of the drug products.
Biopharmaceutics involves factors that influence-
(1) the design of the drug product,
(2) stability of the drug within the drug product,
(3) the manufacture of the drug product,
(4) the release of the drug from the drug product,
(5) the rate of dissolution/release of the drug at the absorption site, and
(6) delivery of drug to the site of action, which may involve targeting a
localized area (eg, colon for Crohn disease) for action or systemic absorption of
the drug.
The knowledge and concepts of biopharmaceutics and thus have an integral role
in the design and development of new drugs and their dosage forms and
improvement of therapeutic efficacy of existing drugs.
Dosage form
Dosage Form (DF) is defined as the physical form of a dose of a chemical
compound used as a drug or medication intended for administration or
consumption. Common dosage forms include pill, tablet, or capsule, drink
or syrup, aerosol or inhaler, liquid injection, pure powder or solid crystal
(e.g., via oral ingestion or freebase smoking), and natural or herbal form
such as plant or food of sorts, among many others. The route of
administration (ROA) for drug delivery is dependent on the dosage form of
the substance.

3. Page 3 of 6
So , to know properly the relation between biopharmaceutics &
dosage form design some term must be known. These are included:
 Absorption: The process of movement of drug from its site of
administration to the systemic circulation is called as absorption.
 Distribution: distribution is reversible transfer of a drug between the
blood and the extravascular fluids and tissues.
 Elimination: Elimination is the major process for removal of a drug from
the body and termination of its action. It is defined as the irreversible loss
of from the body. Elimination occurs by two processes viz.
biotransformation and excretion.
 Biotransformation of drugs is defined as the conversion from one
Chemical form to another. The term is used synonymously with
metabolism.
 Excretion is defined as the process whereby drugs and/or their
metabolites are irreversibly transferred from internal to external
environment.
 Therapeutic efficacy: Therapeutic efficacy describes the maximum
response that can be achieved with a drug.
 Schematic Representation of drug activity is:
First, the drug in its dosage form is taken by the patient either by an oral,
intravenous, subcutaneous, transdermal, etc, route of administration. Next, the
drug is released from the dosage form in a predictable and characterizable
manner. Then, some fraction of the drug is absorbed from the site of

4. Page 4 of 6
administration into either the surrounding tissue, into the body (as with oral
dosage forms), or both. Finally, the drug reaches the site of action.
A pharmacologic response results when the drug concentration at the site of
action reaches or exceeds the minimum effective concentration (MEC). The
suggested dosing regimen, including starting dose, maintenance dose, dosage
form, and dosing interval, is determined in clinical trials to provide the drug
concentrations that are therapeutically effective in most patients
Effectiveness of different dosage form
Bioavailability and effectiveness also influenced by some factor which are
influenced ADME in the body . These are : solubility, permeability, chemical
stability, and pharmacokinetics.
 Solubility: The solubility of a drug is an important factor in determining
its appropriate dosage form. A highly soluble drug can be formulated as a
liquid solution, while a poorly soluble drug may require a different form,
such as a solid oral dosage form like a tablet or capsule.
 Permeability: The permeability of a drug through biological membranes
also influences its appropriate dosage form. For example, a drug with low
permeability may require a formulation that increases its permeability,
such as a liposomal or micelle formulation.
 Chemical stability: The chemical stability of a drug is another critical
factor in determining its appropriate dosage form. A drug that is prone to
degradation or oxidation may require a different form than a drug with
good chemical stability.
 Pharmacokinetics: The pharmacokinetic properties of a drug, such as its
half-life, metabolism, and elimination, also play a role in determining its
appropriate dosage form. For example, a drug with a short half-life may
require a more frequent dosing schedule than a drug with a long half-life.

5. Page 5 of 6
Influence of intended therapeutic use on dosage form design: The intended
therapeutic use of a drug also plays a crucial role in determining its appropriate
dosage form. For example, a drug that is intended for oral administration may
require a different form than a drug intended for intravenous administration.
Influence of patient acceptability on dosage form design: The acceptability
of a dosage form by patients is also an important consideration during dosage
form design. A dosage form that is easy to administer and well-tolerated by
patients is more likely to be successful than a form that is difficult to use or
causes adverse effects.
Influence of safety on dosage form design:
Safety is a key consideration during dosage form design. A dosage form that
poses a risk of adverse effects, such as a form that is easily broken or
contaminated, is not appropriate for use.
Among the different dosage form liquid dosage form are more readily absorbed
then solid and semisolid dosage form ,because it skip the disintegration step and
produce faster dissolution then other dosage form .So , a patient to obtain exact
therapeutic activity must be maintained proper dose and proper dosage form by
which they get easily MEC . It should also be considered that must not produce
toxic effect due to accumulation in the body . So it should maintain optimum
elimination rate. As a general rule, the bioavailability of a drug from various
dosage forms decreases in the following order:
Solutions > Emulsions >Suspensions > Capsules> Tablets > Coated Tablets
> Enteric Coated Tablets Sustained Release Products.
Thus, absorption of a drug from solution fastest with least potential for
bioavailability problems whereas absorption from a sustained release product is
slowest with greatest bioavailability risk.
After all if a proper drug design can be achieved , a good dosage regimen can be
established . Cause Biopharmaceutics provides the scientific basis for drug
product design and drug product development. Each step in the manufacturing

6. Page 6 of 6
process of a finished dosage form may potentially affect the release of the drug
from the drug product and the availability of the drug at the site of action.
Faster the drug release rapid absorption which enhance bioavailability means
rate and amount of drug that reaches the systemic circulation and maintain
proper drug concentration in the blood.
Biopharmaceutics considers the properties of the drug and dosage form in a
physiologic environment, the drug's intended therapeutic use, and the route of
administration. Both the pharmacist and the pharmaceutical scientist must
understand these complex relationships to objectively choose the most
appropriate drug product for therapeutic success.