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Lab.2

-year class

Practical Pharmacology

2010-2011

Dosage Forms

Dr. Mohammed Qasim

Dr. Huda Ibrahim

I.Oral

1.Tablets:-

the most common preparation for oral use . Is

made by   compressing the drugs   &   inert
binders  as  starch   or  lactose into hard mass
which disintegrate in water . A tablet before
being   absorbed should   disintegrate   into
granules& then dissolute into primary drug
particles

The active substance in an oral solid dosage

form such as tablet represents only a small

proportion of the total weight

• .

These include:-

diluents(Lactose, Calcium, Sulphate), binding

agents(bentonile), lubricants(talc), disintegrating

agents (starch , mixture of sodium bicarbonate &

tartaric acid), coating formulation . material

(sugar), special

Different manufacturing procedures may result in

the production of different physical forms of the

active drug(e.g. compression force & tablet

hardness).

Coated tablets:-

a common type is a sugar coated tablet.

The coat is an additional physical barrier
for disintegration.

1-Coatings are used to mask the unpleasant

tastes & odors.

2-To protect the tablet ingredients from

decomposition in drug storage.

3-To improve the appearance of the tablet

Enteric-coated tablet:-

a special film coat

designed to resist gastric fluid & disrupt or

dissolve in the intestine

1-They are used to protect a drug from

degradation in the stomach.

2-To minimize gastric irritation caused by

some drugs

Sustained-release tablets(SR)

this is designed to release their

contents over extended period of
time.

Advantages:

to eliminate the need for multiple dosage

regimens , particularly   for these drugs
requiring    reasonably constant   blood  level
over  a long period of time , or drugs which
need to be given in  high doses , but  too
rapid release   is   likely   to   cause
undesirable  side effect

(e.g. potassium chloride tablets)

2.Capsules:-

a drug formulation encapsulated in a hard

gelatin shell .Drug particles in the capsule
are   not   subjected   to   high compression
that  tend to compact the powder & to
reduce the effective surface area. However,
drug bioavailability from capsule isn't always
better than a tablet.

Advantages:

1.Protection from light.
2. Mask the taste or odour of their components.
3. Attractive appearance.
4. Ease to identify.
5. Controlled release.

Spansule:

capsule containing drug granules with

special pharmaceutical formulation to be
disintegrated and dissolved in different times
for prolonged action (theophyllin)

3.Granules:-

all irregular particles of drug, sugar & inert

adjuvant stirred in water before taking

4.Effervescents tablet or

granules:-

the basis of the effervescence is a mixture

of citric acid & tartaric acid with sodium
bicarbonate .  When dissolve in water , the
acid & bicarbonate react together to
produce carbonic acid . The carbonated water
partly  disguises the unpleasant  taste   of
drug   & has refreshing properties.

5.Syrup:-

is a concentrated aqueous solution of sugar ,

useful vehicle for water soluble drugs act
both as a solvent & flavoring agent .

Advantages:

1. Immediately available for absorption. 2.

Useful for children or in swallow difficulties
(elderly).

6.Elixir:-

is a sweetened hydro alcoholic solution

that contains approximately 25%. It is a
suitable vehicle for drugs soluble in either
water or dilute alcohol.

7.Linctuses:-

are viscous liquid oral preparations that are

usefully prescribed for the relief of cough

II.Topical:-

1.Aerosols:-

they are suspensions of fine solid or liquid

particles in a gas . They are used to  the
respiratory tract or skin . The sprays used to
treat respiratory diseases are  atomized   in
devices   known   as nebulizers

2.Gargles:-

they are aqueous solutions used to treat or

prevent throat infections, usually dispensed
in concentrated form to be diluted in warm
water before use

3.Drops:-

could be to the eye, ear, nasal or oral drops.

Nasal drops are usually aqueous because oily
drops inhibit movement of cilia in the nasal
mucosa & if used for a long time , they may
reach the lungs & cause lipoidal pneumonia

4.Ointments:-

are semisolid, greasy preparations for

application to the skin , rectum . The base is
usually anhydrous & contains the medicament in
solution or suspension.

5.Cream:-

they are semisolid solution for external use. They

are 2 kinds:-1. aqueous cream 2. oily cream.

In which the emulsions are oil in water or water in

oil respectively

Ointment

Cream

1-greasy

1-relatively not greasy

2-semisolid anhydrous

2-semisoilid emulsion(oil +
water)

3-less skin penetration

3-more skin penetration

4-used for dry, chronic skin
lesion

4-used for wet lesions of
skin

5-applid to skin & rectum

Applied to skin only

6.Lotions:-

aqueous preparations for external

application without friction . They are
rubbed on skin or applied on the suitable
dressing

7.Suppositories:-

are conical or ovoid solid preparations for

insertion into the rectum, where they exert
local or less often systemic effect. Their base is
fat, wax or glycerol gelatin

8.Pessaries:-

solid medicated preparations for

introduction into vagina where they melt or
dissolve & exert a local action

III.Injections:-

drugs given by injections act more rapidly &

reliably, thus more useful for emergency
situations . They require some technical
skills, aseptic technique & suitable
equipments

a. Injection:

highly purified & sterile dosage form either in

ampoules or vials (for multidose)

b. Intravenous Admixture:

(i.v. fluid) large volume injection intended to be

administered by i.v. infusion , for fluid replacement   ;
electrolytes  balance restoration;   supplementary
nutrition; & as vehicle   for other   drug substance
(G/W, Albumin, Dopamine).