2. The dosage forms may be classified in a
number of ways as below
1.Formwise
2.Routewise
3.Release Rate/Target wise
3. Formwise dosage forms may be classified as;
1.Solid Dosage Forms
2.Liquid Dosage Forms
3.Semi-solid Dosage Forms
4. The solid dosage forms manufactured these
days are mostly unit dosage form , i.e they
consist of doses which are taken by numbers
However some solids are packed and
supplied in bulk and the patient has to
measure out the medicine from the bulk
package each time he has to use it
5. The unit dosage forms are marked as pills ,
tablets,capsules,cachets or wrapped powders.
The bulk forms meant for internal use are
supplied either as granules or as fine
powders
Some solids meant for use as snuffs or
powders for use in ophthalmic cavity etc.are
microfine products.
6. The products for external use such as dusting
powders or powders meant for application to
the wounds or tooth powders are generally
supplied as fine powders.
7.
8.
9.
10.
11. The liquid dosage forms whether for internal
parenteral or external use may be either
monophasic or biphasic products.
Monophasic products are represented by true
or colloidal solutions and solubilised
preparations.
They all appear to be similar in physical
appearance and consist of only one phase.
They may be having water as the solvent or
may be occasionally based on some other
fluid.
12. The biphasic products are exemplified by
emulsions and suspensions and consist of
two phase.
In emulsions generally both the phase are
liquids while in suspensions the continuous
phase is liquid and the disperse phase consist
of finely divided solids.
13.
14.
15. Semi-solid dosage forms are mainly meant
for external use and are exemplified by
ointments,creams,pastes,jellies etc.
Suppositories which represent unit dosage
forms may be also be included under this
category.
Semi-solid products for internal use are very
rare in allopathic system in medicine.
16. Electuaries could possibly be included in this
category.
However such products are quite popular in
Ayurvedic system of medicine and are known
as Avelehas.
Chavanprash is an exampl of products of this
kind
17.
18.
19. The Tools for structure Dosage Forms
A substance added to something in small
quantities, typically to improve or preserve it.
1.Form givers/Form stablisers
2.Form Disintegrators
3.Solvent/Bases/Vehicles/Diluents
4.Organoleptic Additives
5.Formulation Stabilsers
6.Manufacturing Additives
20. A number of additives are included in
formulation with a view to give them a certain
physical form.
Further on many occasion a given formulation
may have a desired physical form to begin
with, which may not be stable on a time scale
warranting inclusion of some additives to
preserve it.
21. Surfactants and hydrocolloids are two groups
of additives that are used as form givers and
form stabilisers.
Example may be quoted form emulsions and
suspensions whose physical forms are mainly
dependent upon the presence of surfactants
and hydrocolloids.
22. On occasions a formulation is given a definite
physical form but to give up its drug contents
to the body , the form must disintegrated into
smaller particles.
Tablets are examples of formulation of this
kind in in which disintegrating agents have to
be necessarily incorporated
23. These terms are often used in different
physical contexts and sometimes carry a
definite ‘ sense ’ but all of them form the
bulk of formulation and help to give it the
desired dimensions.
Solvents generally refer to liquids which are
used for formulation of drugs.
24. The bases are semi-solid materials used for
formulation of ointments, suppositories etc.
Vehicles is a loose word and it may be used
for any material, solid, semisolid or liquid,
which is employed for carrying a drug.
Diluent is often used for materials which are
specifically added to give the drug a bulk or
to reduce concentration.
25. Organoleptic additives may be described as
materials, which when incorporated into a
preparation, confer qualities, which make it
more acceptable to the human senses.
Every manufacturer of medicines considers it
a duty and a necessity to make his
preparation appealing to the sense and tries
to give it one or all of the following
characteristics
27. A stabiliser should be looked upon as a
material that stabilises a particular product
and helps to maintain status quo.
With particular reference to pharmaceutical
formulations, a stabiliser refers to materials
that afford the dosage form chemical stability
and antimicrobial compounds of stalling
microbial growth in the preparations.
28. Manufacturing additives may be defined as
inclusions intended to facilitate the
processing of a given dosage form.
Such additives are generally needed in the
preparation of compressed tablets and
capsules.
29. The most classical example of additives of
this category are glidants, lubricans and
antidhesives which facilitate uniform flow of
granules into the dies, ejection of
compressed tablets and reduce their
tendancy of adherence to faces of punches.
30. In conclusion it may be said that the two
components of dosage form, the drug and
additives, must be given due consideration
related to the properties of the drugs and a
few important categories of pharmaceutical
additives are discussed in the succeeding
chapters
