student use

1. The Need for Dosage Forms
The potent nature and low dosage of most of the drugs in use today preclude
any expectation that the general public could safely obtain the appropriate
dose of a drug from the bulk material. Most drug substances are administered
in milligram quantities (microgram also), much too small (not workable /
practicable) to be weighed on anything but a sensitive prescription or
electronic analytical balance.
EXAMPLES OF
LOW-DOSAGE
DRUGS
MANUFACTURED
INTO CAPSULE
OR TABLET
DOSAGE FORMS
RVKeny Consulting.....

2. Besides providing the mechanism for the safe and convenient delivery of accurate dosage,
dosage forms are needed for additional reasons:
•To protect the drug substance from the destructive influences of atmospheric oxygen or
humidity (coated tablets, sealed ampules)
•To protect the drug substance from the destructive influence of gastric acid after oral
administration (enteric-coated tablets) so also to protect the GI linings against the irritant
effect of drugs
•To conceal the bitter, salty, or offensive taste or odor of a drug substance (capsules,
coated tablets, flavored syrups)
•To provide liquid preparations of drug substances, either as dispersions (suspensions) or as
clear preparations (solutions)
•To provide rate-controlled drug action (various controlled-release tablets, capsules, and
suspensions)
•To provide optimal drug action from topical administration sites (ointments, creams,
transdermal patches, and ophthalmic, ear, and nasal preparations)
•To provide for insertion of a drug into one of the body’s orifices (rectal or vaginal
suppositories)

3. • To provide for placement of drugs directly in the bloodstream or body tissues (injections)
• To provide for optimal drug action through inhalation therapy (inhalants and inhalation
aerosols)
General Considerations in Dosage Form Design
Before formulating a drug substance into a dosage form, the desired product type must
be determined insofar as possible to establish the framework for product development.
Then, various initial formulations of the product are developed and examined for desired
features (e.g., drug release profile, bioavailability, clinical effectiveness) and for pilot plant
studies and production scale-up.The formulation that best meets the goals for the product
is selected to be its master formula. Each batch of product subsequently prepared must
meet the specifications established in the master formula.
There are many different forms into which a medicinal agent may be placed for the
convenient and efficacious treatment of disease. Most commonly, a manufacturer prepares
a drug substance in several dosage forms and strengths for the efficacious and convenient
treatment of disease (Fig. 4.1). Before a medicinal agent is formulated into one or more
dosage forms, among the factors considered are the physical and chemical properties of
the drug substance and various therapeutic considerations.

4. RVKeny Consulting.....

5. Solutions
Tinctures
Spirits / Essences
Solutions
Tinctures
Sterile
STERILE LIQUIDS
Monophasic (Eye Drops,
Injections / Infusions)
Aromatic
Waters
Glycerites /
Glycerins

9. OINTMENTS- are homogenous, translucent, viscous, semi solid preparation
intended for external application to skin or mucous membranes.
CREAMS - A semisolid dosage form containing one or more drug substances
dissolved or dispersed in either a water-in-oil emulsion or an oil-in-water or in
an other type of water-washable base.
Viscous semi solid emulsion with opaque appearance as Contrasted with
translucent ointments.
Consistency depends on whether the cream is W/O or O/W.
PASTES - are semisolid preparations intended for external application to
skin.
The pastes are generally very thick & stiff.
They do not melt at ordinary temperature & thus forms a protective coating
over the area where they are applied.

10. GELS -are semisolid systems in which a liquid phase is constrained within a
3D polymeric matrix (consisting of natural or synthetic gums) in which a
high degree of physical/chemical cross-linking has been introduced.
Gels are aqueous colloidal system of hydrated forms of insoluble
medicaments.
Jellies are transparent or translucent, non greasy, semi solid preparations
mainly used for external application to skin.
These are also used for lubricating catheters, surgical gloves & rectal
thermometer.The substance like gelatin, starch, tragacanth, sodium
alginate & cellulose derivatives are used for the formulation of jellies.
Jellies are of three types namely as
Medicated jellies
Lubricating jellies
Miscellaneous jellies - carrier for spermicidal agents to
be used intra vaginally with diaphragm.

12. POULTICES- These are also known as cataplasms.
They are soft viscous wet masses of solid substances applied to skin in order
to reduce inflammation and in some cases to act as a counter irritant.
Poultices must retain heat for a considerable time.
After heating the preparation is spread on dressing and applied to the
affected area .
E.g: Kaolin poultice (B.P.C)

13. PLASTERS-These are solid or semi solid masses
adhere to the skin when spread up on cotton felt line
or muslin as a backing material.
made by incorporating medicaments in the resinous
or waxy bases which are melted or spread on
suitable baking material..
They are generally used to,
Afford protection and medicinal support.
Perform on occlusive and macerating action.

15. SUPPOSITORIES- It is solid or stiffened semi solid dosage form intended to
insertion on body orifices other than mouth where they melt , soften and
dissolve and exert local or systemic effect.
TYPES-Rectal suppositories
Pessaries (vaginal)
Urethral bougies
Nasal bougies
Ear cones

16. Oral solutions
Elixirs
Linctuses
Syrups
Mixtures
Draughts
Spirits
Paediatric drops
SOLUTIONS AS DOSAGE FORMS : defined as monophasic liquids containing
one or more soluble chemical ingredients dissolved in a suitable solvent and
which do not by the reason of their ingredients or by the method of their
preparation fall into another category of LDFs.
Gargles and mouthwashes
Enemas and douches
External solutions
Lotions
Liniments
Applications
Collodions

17. GLYCERO-GELATINS: Glycerogelatins are plastic masses containing gelatin
(15%) , glycerin (40%) , water (35%) and an added medicinal substance (10%)
such as zinc oxide.
Soften the gelatin in water bath for 10 minutes, then heat it on steam bath
until gelatin is dissolved.
Mix the medicinal substance with glycerin and mix with gelatin.
Cool by stirring and congeal.
Before application it is melted and then cooled just above body temperature
and applied on the affected area with a fine brush.
Covered with bandage and allowed to remain in place for weeks.

18. Advantages and disadvantages of Solutions as dosage forms
DSADVANTAGES
Drug stability often reduced in solution
Bulky, difficult to transport and prone to container
Breakages
Technical accuracy needed to measure dose on
Administration
Measuring device needed for administration
Some drugs poorly soluble
ADVANTAGES
Drug available immediately for absorption
Flexible dosing
May be designed for any route of administration
No need to shake container
Facilitates swallowing in difficult cases

19. General principles of solution preparation:
Historically, a range of solutions have been developed in order to fulfil a wide variety of
pharmaceutical functions. It is therefore common to find solutions classified according to
their intended use (e.g. oral internal, topical, ophthalmic, nasal or parenteral), by the
nature of their formulation (e.g. simple or complex), or to be categorised by a traditional
name that relates to the solvent system used and/or their intended function (e.g. spirits,
tinctures, aromatic waters, syrups and elixirs). Although the precise characteristics of
different types of solution may vary, the essential principles governing their preparation
remain similar. The two key characteristics that need to be considered when compounding
solutions are solubility and stability.

20. Solubility
The following points relating to the solubility of the drug element(s) of the formulation need to be taken into
consideration:
* Will the drug(s) dissolve in the solvent or a component of the solvent system?
* What quantity of drug will dissolve?
* How long will dissolution take?
* Will the drug(s) remain in solution and for how long?
* What is the pH of solvent required for dissolution?
When preparing a solution, the solid(s) will need to go through a dissolution phase. During compounding, it is
worth remembering that dissolution rates generally increase with:
* smaller particle sizes
* effective stirring
* lower viscosities
* increased temperature.
Stability
In addition to the solubility of the drug element(s) of the formulation, other considerations regarding the physical
stability of the preparation will need to be taken into consideration (e.g. temperature variation, photosensitivity,
etc.), as will the chemical stability and time period, and the microbiological stability and need for a preservative.

21. “LINCTUSES are viscous, monophasic liquid preparation containing a high
concentration of syrup intended to sipped and swallowed slowly for treatment
of cough.”
ELIXIRS: sweet, flavoured, MLDFs containing one or more soluble medicinal
agents dissolved in a hydro alcoholic vehicle and meant for internal use.They
may contain other liquids like propyene glycol, glycerol etc.
AOMATIC WATERS: MLDFs containing aromatic principles and meant to be
used as Carminative or as flavouring vehicles.
TINCTURES: MLDFs containing a medicament or mixture of medicaments
dissolved in a hydroalcoholic vehicle and meant for internal as well as external
use. Alcohol ranges from 15% to 25%.
Syrups- sweet, viscous, flavoured MLDFs containing sucrose solution as a base
into which medicaments are dissolved. Simple syrup IP contains 66.7% w/w
sucrose, USP Syrup- 85%v/v sucrose

22. Draughts- A draught is an older term used to describe a liquid preparation formulated as a
single dose, in a volume which is larger than generally utilised in traditional mixture
formulations. Each draught was usually supplied in a 50mL unit dose container.
Spirits- Spirits are solutions containing one or more active medicaments dissolved in either
absolute or dilute ethanol.
Paediatric drops- These are an oral liquid formulation of potent drugs
usually in solution, intended for administration to paediatric patients, though they may be
useful in other patients with swallowing difficulties.The formulation is designed to have very
small dose volumes which must be administered with a calibrated dropper.
Gargles and mouthwashes- Gargles and mouthwashes are aqueous solutions that are
intended for treatment of the throat (gargles) and mouth (mouthwashes) and are generally
formulated in a concentrated form.These preparations must be diluted before use and care
should be taken to ensure that appropriate instructions are included on the label and that the
container used will be easily distinguishable from those containing preparations intended to
be swallowed.
Enemas and douches- These liquid preparations are often formulated as solutions (though
they may be presented as an emulsion or suspension) and are intended for instillation into the
rectum (enema) or other orifice, such as the vagina or nasal cavity (douche).The volumes of

23. these preparations may vary from 5mL to much larger volumes.When the larger volumes
are used it is important that the liquid is warmed to body temperature before
administration.
External solutions- As with internal solutions, owing to the versatility of the solution, a
number of different preparation types have been developed for external use.
Lotions
Lotions are solutions, but may also be suspensions or emulsions, that are intended to be
applied to the skin
without friction on a carrier fabric such as lint and covered with a waterproof dressing. In
some cases lotions are applied to the scalp, where the vehicle for the medication is alcohol
based, allowing for rapid drying of the hair and thus making the product more acceptable
to the patient (e.g. Salicylic Acid Lotion2% BPC). In these cases, problems of flammability
are addressed by suitable labelling.
Liniments
A liniment is a liquid preparation intended to be rubbed with friction and massaged onto
the skin to obtain analgesic, rubefacient or generally stimulating effects. Liniments should
not be used on broken skin.They are usually solutions of oils, alcohols or soaps, but may be
formulated as emulsions.

24. Applications
Applications are solutions, though they may also be suspensions or emulsions, intended to be
applied without friction to the skin and to be used without any dressing or covering material.
Collodions
These are principally solutions of pyroxylin in a vehicle of ether and alcohol that are
intended to be painted onto the skin and left to dry.When dry, the collodion leaves a flexible
film of cellulose on the skin which may be used to seal minor injuries or retain a dissolved
drug in contact with the skin for an extended period.
Collodions are highly volatile and highly flammable and care should be taken to label any
preparation appropriately.

25. New Drug Development and Approval Process

28. Site of application /
administration

29. Time course of the drug in the body
Blood, Serum,
or Plasma
Concentration-
Time Curve