Page 34 - Course Guide 2019

9 NON-STERILE DOSAGE FORMS

For the purpose of this course, the most important non-sterile preparations that will be covered
include internal liquid preparations, oromucosal preparations, external liquid preparations,
suspensions, emulsions, powders and granules, capsules, tablets, suppositories and
pessaries, creams, ointments, pastes and jellies. This chapter will discuss in brief about all of
these preparations. The details will be further elaborated during the respective lecture
sessions.

9.1 SOLUTIONS, ELIXIR, LINCTUS
Solutions are clear liquid solution, containing one or more soluble ingredients in water as the
carrier. They may be used either for internal or external applications, and maybe sterile or
unsterile, depending on their purpose.
Elixirs are clear, nicely flavoured preparations, which contain high amount of alcohol, sugar,
glycerol and/or propylene glycol, with colouring agent and suitable flavouring agent.
Sometimes preservatives may be added. Due to the high content of sugar and alcohol,
microorganisms usually could not grow in elixirs, unless they are being diluted with water.
Thus, diluted elixirs should not be kept for more than two weeks.

Linctuses are viscous liquid solutions usually made with a very high content of sucrose, with
specific properties of demulcent, expectorant or sedative. They should be swallowed without
water.

Solubility of ingredients are usually being described as follows:

Description Definition
Very soluble 1 part is soluble in less than 1 part of solvent
Freely soluble 1 part is soluble in 1 – 10 parts of solvent
Soluble 1 part is soluble in 10 – 30 parts of solvent
Sparingly soluble 1 part is soluble in 30 – 100 parts of solvent
Slightly soluble 1 part is soluble in 100 – 1000 parts of solvent
Very slightly soluble 1 part is soluble in 1000 – 10000 parts of solvents
Practically insoluble 1 part is soluble in more than 10000 parts of solvents

For drugs with disagreeable taste, flavouring agents can be used to mask the bad taste and
increase patients’ compliance. The following are some basis on choosing flavours for liquid
preparations:

Taste Flavour
Sour Lemon, orange, lime, cherry, raspberry
Bitter Coffee, chocolate, cherry, raspberry, orange, lemon, lime, mint