Dr. Mohammad Javed Ansari, PhD.

Contact info:

javedpharma@gmail.com

COLLEGE OF PHARMACY

PHARMACEUTICS II

(PHT 312)

OBJECTIVES OF THE LECTURE

At the end of this lecture, you will be able to explain:

What are non- aqueous Solutions?

Why non- aqueous vehicle are used?

What are various types of non- aqueous Solutions?

What is difference between elixirs and Spirits?

What is difference between lotion and liniments?

What is difference between counter irritant and rubefacient?

What are advantages of non- aqueous Solutions?

What are disadvantages of non- aqueous Solutions?

How non- aqueous Solutions are prepared?

Rationale: Why non-aqueous vehicle??

If the drug is not completely soluble or unstable in aqueous

medium it may be necessary to use an alternative non-aqueous

solvent.

Internal products may contain ethanol, glycerol, propylene

glycol, certain oils.

Solvents such as acetone, benzene and petroleum ether are not

used for internal products.

Types of non-aqueous solutions

1. Alcoholic or hydroalcoholic solutions, e.g. elixirs and spirits,

2. Ethereal solutions, e.g. the collodions

3. Glycerin solutions, e.g. the glycerites,

4. Oleaginous soIutions e.g. the liniments, medicated oils, oleo-

vitamins, sprays, and toothache drops.

3

ELIXIRS

Clear, pleasantly flavored, sweetened hydro-alcoholic liquids intended for oral use.

More preferred than syrups due to the stability character.

Alcohol (10-40 % v/v) is used as a co-solvent to ensure solubility of all ingredients.

The presence of alcohol in elixirs presents a possible problem to pediatric penitents and adults who wish to avoid alcohol.

The inclusion of polyol co-solvents, e.g. propylene glycol, glycerol, enables the concentration of alcohol to be reduced.

Sweeteners, flavours and colours are added to increase the palatability and enhance the aesthetic qualities of the elixirs.

Preservatives are not required in pharmaceutical elixirs that contain greater than 12% v/v alcohol, due to the antimicrobial properties of this co-solvent.

Dexamethasone Elixir USP, Phenobarbital Elixir USP.

ELIXIRS: METHOD OF PREPARATION

1. Simple solution with agitation

2. By the admixture of two or more liquid ingredients

Note: TINCTURES are alcoholic preparations of vegetable drugs (weaker than herbal extracts), prepared by maceration and percolation, or may be prepared by dissolving the corresponding liquid extract of chemical substances (e.g. iodine) in alcohol or hydroalcohol solvent. e.g. Belladonna tincture, Iodine tincture

INCOMPATIBILITY OF ELIXIR

Elixirs are often incompatible with aqueous solutions and hydro-alcoholic solutions with very low alcohol content.

If an aqueous solution is added to an elixir, a partial precipitation of ingredients may occur. This is due to the reduced alcoholic content of the final preparation.

Alcohol precipitates water soluble substances e.g. tragacanth, acacia,

agar and many inorganic salts from aqueous solutions. 5

SPIRITS

Alcoholic or hydroalcoholic solutions of volatile

substances. The active ingredient may be gas, liquid

or solid.

Generally, the alcoholic concentration of spirits is

rather high.

Spirits may be used internally for their medicinal value,

by inhalation but is mostly used as flavouring agents.

Spirits should be stored in tight, light-resistant

containers and in a cool place, WHY?

Spirits are preparation of high alcoholic strength and

when diluted with aqueous solutions or liquids of low

alcoholic content turbidity may occur, WHY?

6

SPIRITS: METHOD OF PREPARATION

Simple Solution

Majority of spirits are prepared by dissolving the solute in

alcohol by agitation. Filtration is generally desirable to obtain a

sparking clear product.

Example: Aromatic Spirit - 62 to 68% hydroalcoholic solution of

ammonia and ammonium carbonate flavored and perfumed with

lemon, lavender and myristica oil.

Solution with Maceration

Macerate the vegetable materials in a suitable solvent to

remove the undesired constituents or to extract one which is

desired.

Example: Peppermint Spirit (Spiritus Menthae Piperitae) – 79 to

85% hydroalcoholic solution containing 10% peppermint oil

Use: digestive aid or carminative 7

COLLODIONS

Are liquid preparations containing pyroxylin (a nitrocellulose) in

a mixture of ethyl ether and ethanol.

They are applied to the skin by means of a soft brush or other

suitable applicator and, when the ether and ethanol have

evaporated, leave a film of pyroxylin on the surface.

Collodion, USP is a clear or slightly opalescent viscous liquid

prepared by dissolving 4% W/V pyroxillin in 3:1 mixture of ether

and alcohol.

Flexible Collodion, USP is prepared by adding 2% of Camphor

and 3% castor oil to the Collodion.

The official medicated collodion, Salicylic Acid Collodion USP,

contains 10 % w/v of Salicylic Acid in Flexible Collodion USP

and is used as a keratolytic agent in the treatment of corns and

warts.

8

GLYCERITES

Glycerins or glycerites are solutions or mixtures of

medicinal substances in not less than 50% by weight

of glycerin.

Most of the glycerins are extremely viscous.

Glycerin is a valuable pharmaceutical solvent forming

permanent and concentrated solutions.

Glycerin is used as the sole solvent for the preparation

of Antipyrine and Benzocaine Otic Solution USP.

As noted under Otic Solutions, glycerin alone is used

to aid in the removal of cerumen.

Glycerins are hygroscopic and should be: stored in

tightly closed containers. 9

Paints

Paints are liquids for application to the skin or mucous

membranes.

Skin paints contain volatile solvent that evaporates quickly to

leave a dry resinous film of medicament.

Throat paints are more viscous due to a high content of glycerol,

designed to prolong contact of the medicament with the affected

site.

LOTIONS

Lotions are liquid preparations for external application without

friction.

They are either dabbed on the skin or applied on a suitable

dressing and covered with a waterproof dressing to reduce

evaporation.

10

LINIMENTS

Are alcoholic or oleaginous solutions or emulsions of various

medicinal substances.

Alcoholic liniments are used generally for their rubefaciant and

counterirritant effects. Such liniments penetrate the skin more

readily than do those with an oil base.

The oily liniments are milder in their action and may function

solely as protective coatings.

Liniments are intended for external application and should be so

labeled.

They are applied with rubbing to the affected area, the oil or

soap base providing for ease of application and massage.

Liniments should not be applied to skin that are bruised or

broken.

11

Rubefacient

A medicine for external application that produces redness of the

skin. e.g. by causing dilation of the capillaries and an increase

in blood circulation.

Counterirritant

A medicine applied locally to produce superficial inflammation in

order to reduce deeper inflammation.

OLEO VITAMINS

Oleo vitamins are fish liver oils diluted with edible vegetable oil

or solutions of the indicated vitamins (usually vitamins A and D).

The indicated vitamins are unstable in the presence of rancid

oils and, therefore, those preparations, should be stored in

small, tight containers, preferably under vacuum or under an

atmosphere of an inert gas, protected from light.

12

THANK YOU FOR ATTENTION

GOOD LUCK ..