College of Medicine and Health Sciences

Department of Pharmacy

Pharmaceutical Solutions
By: Tsegaye N. (B. Pharm, MSc)
tsega1994et24@gmail.com

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Out Line

 Introduction
 Formulation of solutions (API and Excipients)
 General methods of preparation
 Solutions taken orally
 Solutions used in the mouth and throat
 Solutions instilled into body cavities
 Topical solutions
 Injectables (sterile products)

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Introduction

Liquid Dosage
Forms

Monophasic
Liquid DFs Poly-phasic
(Solutions) Liquid DFs

Aqueous Non-aqueous Colloids

solutions solutions Suspensions Emulsions

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Introduction…

 Solution: solutions are clear Liquid preparations containing one or more active
ingredients dissolved in a suitable vehicle.
 Colloids: A system in which finely divided particles, which are 1 nm - 0.5µm in
size, are dispersed within a continuous medium in a manner that prevents them
from being settled rapidly.
 Suspension: (Solid in Liquid dispersion) Liquid preparations containing one or
more active ingredients suspended in a suitable vehicle.
 Emulsion (Liquid in Liquid dispersion): Emulsions are two phase system in which
one liquid is dispersed through out another liquid in the form of small droplets

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Introduction…
 Solution:
 Is a homogeneous mixture composed of two or more substances
 One substance (solute) is dissolved in another substance (solvent).
 The solute is the component present in the smallest amount
 The solvent is the larger liquid component.
 The solute is dispersed throughout the solvent in molecular or ionic sized particles.
 It is a thermodynamically stable, one-phase system.

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Introduction…
 Steps in making a Solution
 Breaking up the solute into individual components:
=>expanding the solute
 Overcoming intermolecular forces in the solvent to make room for the solute:
=>expanding the solvent
 Allowing the solvent and solute to interact
=> form the solution

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 Advantages and Disadvantages

 Advantages  Disadvantages
 Ease of administration  They are less stable than solid DFs.
 Faster absorption.  Unpleasant flavours can be difficult
 Uniform dosage. to mask.
 Provide safe means of administering  They are bulky to transport.
certain substances  A spoon is needed to administer the
 like potassium iodide and bromide dose.
that cause gastric pain if taken dry.  Accidental breakage to the container
 Have attractive appearance- results in complete and messy loss of the
 psychological effect. contents..

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Classification of Solutions
 Based on route of administration

Pharma Solutions

Used in the mouth Instilled into Applied to body

Taken orally and throat body cavities surfaces
 Syrups  Mouth Washes  Douches  Collodions
 Elixirs  Gargles  Enemas  Liniments
 Spirits  Throat Paints  Ear Drops  Lotions
 Linctuses  Throat Sprays  Nasal Drops  Paints
 Nasal Sprays

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Classification of Solutions…

Based on vehicle used

Pharma
Solutions

Aqueous solutions Sweet or Viscid Non-aqueous solutions

 Douches

 Elixirs
Enemas  Syrups
 Gargles  Spirits
 Mouth washes  Collodions
 Nasal Washes  Glycerins
 Sprays  Lotions
 Otic Solutions  Liniments
 Inhalations

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Pharmaceutical Applications
Solutions have a wide variety of uses in They are also used as:
the pharmaceutical industry.
 Flavorings
They are used therapeutically as
vehicles for:  Buffers

 Oral  Preservatives and

 Parenteral  Suspending agents for a variety of
liquid dosage forms
 Topical
 Otic
 Ophthalmic
 Nasal products

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Solvents for solution preparation
 Solvent selection is based on:
 Solubility
 Clarity
 Toxicity
 Viscosity
 Compatibility with excipients
 Chemical inertness
 Palatability
 Odor
 Color and
 Economy.
In most cases,
Water is the preferred solvent.
It meets the majority of the above criteria.
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Solvents for solution preparation…

Water:
 The major ingredient in most of liquid dosage forms is water.
 It is used both as a vehicle and as a solvent.
 Advantages:
 Tastelessness,
 Freedom from irritating qualities and
 Lack of pharmacological activity make it ideal for such purposes.

 Disadvantages:
 Favorable medium for some chemical reactions, and
 Supports the growth of microorganisms when contaminated.
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Solvents for solution preparation…
 The USP recognizes six types of water for the preparation of dosage forms.
1) Purified water
2) Water for injection
3) Sterile water for injection
4) Bacteriostatic water for injection
5) Sterile water for inhalation
6) Sterile water for irrigation

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Solvents for solution preparation…

 Purified water:
 The preferred and most commonly used vehicle in the solutions.
 The source or feed water for the production of purified water is drinking water.
 It must meet the requirements for ionic and organic chemical purity
 It must be protected from microbial contamination.
 It should be protected from recontamination and microbial
proliferation.
 It is used in as an excipient in the
o Production of non-parenteral and non ophthalmic products.

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Cont…
 It is also used for
 cleaning of certain equipment’s and non-parenteral product-contact
components.
 Commonly produced by:
 Ion Exchange
 Reverse Osmosis (RO) and
 Distillation

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Solvents for solution preparation…

A. Distillation
 Separation method based on boiling point
difference.
 Generally, the first portion of aqueous
distillate (10% to 20%) must be discarded
 The last portion of water (10% of the original
volume of water) remaining in the distillation
apparatus must be discarded.

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Solvents for solution preparation…

B. Ion Exchange Method

 The ion exchange equipment generally passes water through a column of cation
and anion exchangers
 Consisting of water insoluble synthetic polymerized phenolic, carboxylic, amino,
or sulfonated resins of high molecular weight.
 These resins are mainly two types:
 The cations, or acid exchangers
 The anions, or base exchangers

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Solvents for solution preparation…

C. Reverse Osmosis
 Cross-flow (or tangential flow) membrane filtration
 A pressurized stream of water is passed parallel to
the inner side of a filter membrane core.
 A portion of the feed water permeates the membrane as
filtrate.

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Solvents for solution preparation…

 Depending on their pore size, cross-flow filter membranes can remove particles
defined in the range of
 Microfiltration (0.1 to 2 μm, e.g., Bacteria);
 Ultrafiltration (0.01 to 0.1 μm, e.g., Virus);
 Nanofiltration (0.001 to 0.01 μm, e.g., Organic cpds in the mwt range of
300 to 1,000); and
 Particles < 0.001μm
 Reverse osmosis removes virtually oall viruses, bacteria, pyrogens, and organic
molecules and 90% to 99% of ions

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Solvents for solution preparation…

 Water for injection (WFI):

 Conforms to the standards of purified water, but is also free of pyrogen.
 It contains no added substances
 May not be sterile
 It is used as a solvent for the preparation of parenteral solution
 Collected in sterile & pyrogen free container (glass or glass lined)
 Clear, colourless, odourless and having a pH of 5 -7.
 Must be used within 24 hour
 For products to be sterilized after preparation.
 Must store in tight container at suitable temperature
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Solvents for solution preparation…
 Sterile Water for injection:
 It is water for injection that is sterilized and packaged in single-dose containers of
type I and II glass.
 Packed in container of 1 Liter or less
 It is designed solely for parenteral use only.
 It contains no antimicrobial agents or other preservatives.
 Due to sterilization may contain slightly more solid content.
 Intended to be used as a solvent, vehicle or diluent for already sterilized & packed
injectable.
 Non-pyrogenic.
 Must be added aseptically
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Solvents for solution preparation…

 Bacteriostatic water for injection:  Intended for small volume injectable

 It is sterile water for injection (multi-dose vials)
containing one or more suitable  Not to be used with large volume
bacteriostatic agents. parenteral (usually with 5ml or less).
 Sterile  Repeated withdrawals may be made to
 Non-pyrogenic dilute or dissolve drugs for injection.
 0.9% (9 mg/mL) of benzyl alcohol  The pH is 4.5 to 7.0
added as a bacteriostatic  It is parenteral preparation
preservative.  Indicated only for diluting or dissolving
 Filled in vials/syringe in volume not drugs
more than 30ml  For intravenous, intramuscular or
subcutaneous injection.
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Solvents for solution preparation…

 Sterile water for inhalation:  Sterile water for irrigation:

 Is water for injection that is  It is water for injection packaged
and sterilized in single-dose
 packaged and rendered sterile
containers
 It is intended for use in inhalators
 It may be larger than 1 L and allow
 It carries a less stringent specification rapid delivery of their contents
for bacterial endotoxins than SWFI
 It is not required to meet particulate
 It contains no antimicrobial agents. matter in injections
 Should not be used for parenteral  It contains no antimicrobial agents
administration. or other added substance.

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Solvents for solution preparation…

 Alcohol:  Glycerin: Mainly used as:

 The second most commonly used solvent  Solvent, Sweetening agent, Antimicrobial
(for many organic compounds) preservative and Viscosity increasing
 A hydro-alcoholic mixture is capable of agent.
dissolving both  Propylene glycol:
 alcohol soluble and water soluble substance.  Solvent, Extractant, and Preservative in a
 Alcohol is often preferred because of: variety of liquid pharmaceutical
formulations, including parenterals
 Is widely used for its miscibility with
water  Can also be used as antiseptics.
 Ability to dissolve many water insoluble
ingredients.
 Also possess an antimicrobial
preservative activity.
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Formulation and manufacturing considerations

 Formulation considerations:  Manufacturing

1) Solubility Consideration:
2) Stability 1) Raw Materials
3) Preservatives 2) Equipments
4) Pharmaceutical elegance 3) Manufacturing Procedure
 Viscosity modifiers
 Sweetening agents
 Flavoring agents
 Coloring agents

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Formulation considerations

 Solubility:
 Approaches to increase the solubility of the drug:
 pH adjustment: A large number of drugs are either weak acids or weak bases.
 The solubility of these agents can be markedly influenced by the pH of the
environment
 Co-solvency: Weak electrolytes and non polar molecules frequently have poor water
solubility.
 These types of solutes are more soluble in a mixture of solvents than in one solvent
alone.
 This phenomenon is known as co-solvency.

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Formulation considerations
 Micelle solubilization: At high concentration surfactants are forced into water to
form colloidal aggregate known as micelle.
 Drugs get adsorbed into micelle that increase drug solubility.
 Complexation: Solubility of a compound may be increased by complexing with a
complexing agent.
 e.g. solubility of para amino benzoic acid (PABA) may be increased by complexing
with caffeine.
 Micronization: The process involve size reduction of drug particle 1 to 10microns
either by spray drying or fluid energy mill
 Chemical modification of the drug: Poorly soluble drugs are chemically modified
into water soluble derivatives

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Formulation considerations…

 Stability: Instability can be prevented by:

1) Use of buffering agents
A. Chemical stability:
2) Use of antioxidants
Affected by
3) Proper packaging (e.g.: use of
1) pH
amber bottle for light sensitive
2) Temperature products)
3) Ionic Strength B. Physical Stability
4) Solvent effects  A stable formulation retains its viscosity,
5) Light color, clarity, taste, and odor throughout
its shelf life.
6) Oxygen

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Formulation considerations…
 Preservatives:
 Preservatives must have following criteria:
 Effective against broad spectrum of microorganisms.
 Physically, chemically and microbiologically stable for lifetime of the product.
 Non toxic, non sensitizing, soluble, compatible and
 With acceptable taste and odor.
 Types of Preservatives
 Acidic : phenol, benzoic acid, sorbic acid
 Neutral preservatives : chlorobutanol, benzyl alcohol
 Quaternary ammonium compounds: Benzalkonium chloride
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Formulation considerations…
 Pharmaceutical Elegance:
 Viscosity modifiers: Enhance viscosity. E.g.: Povidone, hydroxyethylcellulose
 Sweetening agents: To enhance palatability and mask the taste of the drugs. Eg :
Sucrose, saccharin, aspartame
 Flavoring agents: To mask unpleasant taste
 Coloring agents: To enhance the appearance of the vehicle;
Which matches well with the flavor employed in the preparation . E.g.: green with
mint, brown with chocolate flavor etc.

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Manufacturing considerations
 Raw Materials : Measuring devices for large and small
amount of solids and liquids.
 Incoming raw materials should be
tested as per specifications that is A filtration system e.g. filter press
identity, purity, uniformity and
microbial contamination.
 Cleaning of equipments:-
 All equipments must be thoroughly
 Equipment's :
cleaned and sanitized before use.
 The following types of equipment's
 Disinfectants used: Dilute solutions of
may be used in manufacture of liquid
H2O2, phenol derivatives.
formulations:-
 Sterilized by: Alcohol, boiling water,
 Mixing tanks (SS 316 Stainless Steel)
autoclaving, steam or dry heat.
equipped with an agitator.

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Manufacturing considerations…
 Manufacturing Process:
Process Flow Control Measured Response
Variables
Addition of Raw Materials
(Active +Excipients as per formula)

 Mixing time
Mixing  RPM
cketed vessel with variable speed mixer)  Clarity
 Temp  Viscosity
 Final volume  Assay
Filtration
(Filter Press or cartridge filter)  Pore size
 Filter integrity  Clarity

Filling
(Automatic Filling Machine)  Filling machine speed  Volume

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Preparation of Solutions…

 Methods for preparation of solutions:

1) Simple solutions:
 Prepared by dissolving the solute in most of the solvent,
 Mixing until dissolved, then adding sufficient solvent to bring the solution up to
the proper volume (by stirring or heating).
2) Solution by chemical reaction:
 Are prepared by reacting two or more solutes with each other in suitable solvent.
3) Solution by extraction:
 Drugs often are extracted with water or with water containingother substances.
 Preparations of this type more often classified as extracts.
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Solutions taken orally

 Oral solution absorption from GIT into the systemic circulation

 May be expected to occur more rapidly than suspension or solid dosage forms of the
same medicinal agent.
 Liquid oral solutions are aqueous formulations.
 To be acceptable for patients,
 These must be palatable.
 Flavouring, colouring and sweetening agents are therefore added
 To enhance their appearance and taste.
 The dose is usually in multiples of 5 mL, and/or patient is given a 5 mL spoon with
the solution.
 When smaller volumes are required, oral syringes are used.
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Solutions taken orally

 Solution pH is usually 7.0, although a range of pH 2–9 can be tolerated.

 In formulating or compounding a pharmaceutical solution,
 The pharmacist must use information on the solubility and stability of each solute with
regard to the solvent or solvent system.
 For many medicinal agents, their solubility in the usual solvents are stated in
 The United States Pharmacopeia– National Formulary (USP–NF) as well as in other
reference books.

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Aromatic Water
 Aromatic waters are clear, aqueous solutions saturated with volatile oils or other
aromatic or volatile substances.
 They are used principally as flavored vehicles.
 Their odors and tastes are similar to those of the drugs or volatile substances from
which they are prepared.
 Aromatic waters were prepared from a number of volatile substances
 Includes
 Chloroform water,
 Camphor water,
 Peppermint water and
 Anise water
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Aromatic Water……

 Chloroform water
 Diluted chloroform water is prepared by mixing 1part of double strength chloroform
water (official formulae) and 1part of water.
 Use: preservative, flavor
 Camphor water
 Diluted camphor water is prepared by mixing 1part of concentrated camphor water
(official formulae) and 40 parts of water.
 Use: flavor, mild expectorant

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Aromatic Water……

 Aromatic water will deteriorate with time therefore, should be made in small
quantities
 Protected from intense light and excessive heat by storing in air tight, light
resistant containers.
 If they become cloudy or otherwise deteriorate; they should be discarded.
 Deterioration may be due to volatilization, decomposition or microorganism
growth.

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Aromatic Water……

 There are two official methods of preparation of aromatic waters

A. Distillation process
B. Solution process
A. Distillation process: e.g. Stronger Rose Water NF
 The aroma containing substance should be coarsely ground and mixed with
sufficient quantity of purified water in the distillation unit.
 After distillation any excess oil in the distillate is removed by filtration.

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Aromatic Water……
B. Solution process: e.g. Peppermint water
 Aromatic water may be prepared by shaking volatile substance with purified
water.
 The mixture is set a side for 12 hours & filtered.

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Syrups

 Definition: Syrups are concentrated, viscous, aqueous solutions of 85% sugar

or a sugar substitute with or without flavors and medical substances.
 Classification based on their use:
1. Medicated syrup– When the aqueous preparation contains some added medicinal
substance
2. Non‐medicated/Flavored syrup– contained various aromatic and pleasantly
flavored substances and is intended as a vehicle or flavor for preparations.

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Cont…

 Classification based on their basic formula:

1. Sugar Based syrups– sucrose and dextrose are usually employed in the
preparation of syrups
2. Artificial sweeteners– sugar‐free syrups which are intended as substitute for
 Sugar‐based syrups and are intended to be administered to persons who must regulate
their sugar/calorie intake

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Cont…
 Disadvantages:
 Advantages:
 Delayed onset of action as
 Appropriate for any patient,
absorption takes time
whatever the age is
 The most natural and easiest  Not suitable in emergency and for
route of administration unconscious patients
 Economical and safe to the patient  Not convenient for patients with GI
 No nursing is required (the patient disorder such as diarrheas, constipation,
can take it without help)
ulceration and hyperacidity in stomach
 Liquid DF is expected for certain types
of products like cough medicines  Can’t avoid first pass metabolism

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Cont…

 Components of syrup: Miscellaneous

 Medicinal agent  Special solvents,
 Purified water  Solubilizing agents,
 Antimicrobial preservatives  Thickeners or

 Sweetening agent  Stabilizers

 Viscosity modifiers
 Flavorants
 Colorants

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Components of syrup….
 Antimicrobial Preservatives
 The amount varies with the proportions of water available.
 Among the preservatives, the most commonly used are:
1. Benzoic acid‐0.1% to 0.2%
2. Sodium benzoate –0.1 to 0.2%
3. Combination of methyl, propyl, butyl parabens totaling 0.1%

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Components of syrup….

 Sugar and other sweeteners:  Saccharin sodium is 300 ‐550 time as

sweet as sucrose.
 Sugar and dextrose are mostly used
 It may be used in concentration of 0.1
 The difficulty or problem with to 0.2%
dextrose are as follows:  Characterized by a bitter after taste.
1. Forms saturated solutions at  Sorbitol can also be used as sweetener
70%w/v (less viscous)
2. Dextrose dissolves more slowly
3. Dextrose is less sweet
4. Saturated solution supports
growth of microorganism

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Components of syrup….

 Flavorants for syrup:  Colorants:

 Are used to render the syrup pleasant  To enhance appeal of the syrup,
tasting.  The colorant should correlate with the
 Most syrups are flavored with synthetic flavorant employed.
or naturally occurring flavorants  The colorant used is generally
 E.g. volatile oil, vanillin, and others,  Water‐soluble,
 The flavorants used must possess  Non‐reactive with other
sufficient water solubility components, and
 Stable

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Preparation of Syrups

 Pharmaceutical syrups are produced by mixing purified water, sweeteners, active

ingredients (API), aromas, flavors and other ingredients (thickeners) etc.

Solid Ingredients Dosing systems Production Tanks

Liquid Ingredients

Filling Machine Storage Tanks Filtration

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Syrups…
 Preparation of Syrups:
 Syrups are generally prepared using one of the following four techniques
depending upon the physical and chemical characteristics of the ingredients.
1. Solution with the aid of heat
2. Agitation without heat (simple admixture of liquid components)
3. Addition of sucrose to a prepared medicated liquid or a flavored liquid
4. Percolation method

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Syrups…
 Solution with Heat:
 This is a suitable preparation method if the constituents are not volatile,
degraded by heat, or when it is desirable to make the syrup rapidly.
 Procedure:
 Purified water is heated to 80–85 0C
 After removing from its heat source, sucrose is added with vigorous agitation
 Heat-stable components are added to the hot syrup
 The mixture is allowed to cool

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Syrups…

 Heat labile and volatile components (e.g. alcohol and oil) are added after cooling
to room temp.
 Volume is adjusted to by the addition of purified water.
 Caution: Do not apply excessive heat -inversion of sucrose causing discoloration
 Examples: Acacia syrup, NF; Cocoa Syrup, NF; Syrup USP (85% sugar, made by cold
and hot process, percolation)

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Syrups…
 Agitation without Heat.
 To avoid heat-induced inversion of sucrose
 This method is used for heat sensitive and volatile substances.
Procedure:
1. Take a vessel of greater capacity than the volume of syrup to be prepared
2. Place sucrose and other formulation ingredients in the vessel
3. Dissolve in purified water allowing intense agitation without spillage.
 Examples: Ferrous Sulfate Syrup, Ephedrine Sulfate, Citric acid Syrup, and
Glycyrrhiza Syrup

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Syrups…
 Addition of sucrose to a liquid medication:
 Often used with fluid extracts (tinctures)
 Syrup made in this way usually develops precipitates
 Many such tinctures and fluid-extract contain alcohol-soluble constituents
and are prepared with alcoholic vehicles
 Alcohol is often an ingredient of the liquids, and
 The resinous and oily substances solubilized by the alcohol precipitate when
water is added.
 Examples: Senna Syrup, NF and Cherry Syrup

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Syrups…
 Percolation Method:
 The principle of percolation is used.
 Either purified water or the source of the medicinal component is passed slowly
through a bed of crystalline sucrose, thus dissolving it and forming syrup.
 Procedure:
 Purified water or aqueous solution of a medicating or flavoring liquid is allowed
to pass slowly through a column of crystalline sucrose to dissolve it.
 The percolate is collected and returned to the percolator as required until all of
the sucrose has been dissolved.

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Syrups…

 The sucrose bed should be coarse.

 Shape of the percolator must be cylindrical or cone shaped.
 Example: Tolu Balsam syrup -flavor for cough syrup
 Packaging of syrup:
 Storage of Syrups:
The general process
 Generally, syrups are stored at
 Filling
room temperature in tightly
 Sealing closed bottle.
 Capping
 Coding and labeling
 Wrapping
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Elixirs

 Elixirs are clear, pleasantly flavored, sweetened hydro-alcoholic liquids.

 They are intended for oral use.
 Because of their hydro-alcoholic character, elixirs are better to maintain both water
soluble and alcohol soluble components in the solutions than the aqueous syrups.
 More preferred than syrups due to the stability character.
 Elixirs are less sweet and viscous than syrups
 They contain a lower portion of sugar
 Less effective in masking the taste of medicinal substances

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Elixirs….

 Advantage of elixirs
 Ease of dosage administration to patients who have difficulty swallowing solid
forms.
 Disadvantage of elixirs
 For children and for adults who choose to avoid alcohol is their alcoholic content.

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Elixirs….
 Classification of Elixirs: Based on their use:
Based on the concentration of alcohol:  Flavored elixirs: are non medicated
1) High alcoholic elixirs: 75 - 78 and used as flavors and vehicles
% alcohol  E.g. Aromatic elixir, Isoalcoholic elixir,
1) Low alcoholic elixirs: 8 -10% alcohol Benzaldehyde elixir

NB.: Elixirs containing at least 10-12%  Medicated elixirs: contain potent

alcohol medicament

 Are already “self-preserving”.  E.g. Diphenhydramine HCl elixir,

Phenobarbital elixir, Theophylline Elixir.

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Components of Elixirs

1. Vehicles: 2. Adjuvants:
 Alcohol and water are primary solvents  Used to improve safety, efficacy and
 Alcohol content may vary from 5-40 palatability
%  Chemical stabilizers: Citric acid
 If the concentration of alcohol is and disodium editate in Neomycin
high, aqueous soluble substances Elixir
may precipitate, or
 Preservatives: 20% alcohol, syrup
 If the concentration of water is high, and methyl paraben and propyl
alcohol soluble substances may paraben
precipitate
 Coloring agents: Coal tar dyes
 Sorbitol, glycerin and
propylene glycol are adjuncts.  Sweetening agents: sucrose, sorbitol,
glycerin, saccharin
4/27/2025 Pharmaceutical Solution 59
Elixirs…

 Flavoring agents: Black current syrup, raspberry syrup, lemon syrup and
orange syrup etc
3. Medicinal substances:
 An elixir may contain water and alcohol

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Elixirs…
 Preparation of elixirs:
 Elixirs are usually prepared:
1) Simple solution method with agitation
2) Add mixture of two or more solutions
 Alcohol soluble and water soluble components are generally dissolved separately
in alcohol and purified water, respectively.
 Then the aqueous solution is added to alcoholic solution rather than the reverse, in
order to maintain the highest possible alcoholic strength at all times so that
minimal separation of alcohol- soluble components occurs.

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 When the two solutions are completely mixed the mixture is made to volume with
specified solvent or vehicle.
 Storage:
 Elixirs should be stored in tight, light resistant containers and
 Protected from excessive heat because of their usual content of volatile oil and
alcohol.

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Linctuses:
Definition: Linctuses are viscous, monophasic liquid preparation containing a high
concentration of syrup intended to sipped and swallowed slowly for treatment of
cough.

 Use:  Dosage
Demulcent, The usual dose is 5ml and part of
the doses must be diluted to this
Sedative and
volume.
Expectorant action
Dilutions must be freshly prepared and
 Administration: not more than two weeks supply should
 To obtain and prolong local action, be issued at a time, unless other wise
specified
 Linctuses should be taken undiluted
and sipped and swallowed slowly
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Linctuses….

 Formulation:  Preservatives:
 Vehicles:  High concentration of syrup acting as
preservative,
 The diluent is syrup (Tolu syrup)
 Benzoic acid is used in codeine linctuses.
 In codeine linctuse is chloroform water
is used.  Coloring agents: Coal tar dyes
 Adjuvants:  Flavoring agents:
 Chemical stabilizers: Mostly stable  Black current syrup, lemon syrup,
because of syrup benzaldehyde etc.

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Spirits:
 Alcoholic or hydro-alcoholic solutions of volatile substances.
 Spirits could be classified according to their uses:
 Therapeutic spirits:
 Contain therapeutic volatile substances.
 May be taken orally, applied externally, or used by inhalation.
 When taken orally, they are generally mixed with a portion of water to
reduce the pungency of the spirit.
 E.g. Aromatic spirit of ammonia
 Flavoring spirits :
 Contain flavoring volatile substances.
 E.g. Compound orange spirit, compound cardamom spirit.

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Spirits…

 Volatile substances in the spirits is more  The lowest amount of alcohol found in
than that of aromatic water. internal spirits as (aromatic spirit of
ammonia)
 Spirits could also contain greater
concentration of aromatic substances  Contain 62-68% alcohol
than the corresponding aromatic waters.
 While (camphor spirit) which is used
 Generally, the alcohol concentration of externally
spirits is rather high (usually over 60%).
 When mixed with water or with an
 Because of the greater solubility of aqueous preparation,
aromatic or volatile substances in alcohol  The volatile substances separate from
than in water. solution and
 Amount of alcohol differ from one spirit  Form a milky preparation.
to another
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Spirits…

 Preparation of Spirits:
1) 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
2) Solution with Maceration
 Macerate the vegetable materials in a suitable substance.
 Example: Peppermint Spirit (maceration of peppermint leaves)

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Spirits…
3)Solution by Chemical Reaction
 Preparation of Aromatic Spirit of Ammonia NF,
 Preparation of Ethyl Nitrate Spirit
4)Distillation
 No spirits currently official are prepared by distillation,
 However, two products of historical significance which is official in NF are prepared by
distillation.
 Examples:
 Brandy (48-54% alcohol, distilled from red grapes) and
 whisky (47-53% alcohol, distilled from hops, barley and other grains)

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Spirits….
 Route of administration of spirits:
 Taken orally: Brandy and whisky
 Used by inhalation: Aromatic sprit of ammonia
 Applied externally.
 Uses of official spirits :
 Carminative (aromatic spirit of ammonia)
 Antacid (aromatic acid of ammonia)
 Mild reflex circulatory stimulant (camphor spirit)
 Flavoring agent (cinnamon spirit)
 Storage:
Spirits should be stored in tight, light resistant containers and in a cool place.
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Solutions used in the mouth and throat

 Gargles
 Gargles are aqueous solutions frequently containing
antiseptics, antibiotics and/or anesthetics used for treating the
throat by forcing air from the lungs through the gargle,
 Which is held in the throat; subsequently, the gargle is
expectorated.
 Many gargles must be diluted with warm water prior to use.
 The product should be labeled so that it cannot be mistaken for
preparations intended for internal administration.
 “Not to be swallowed in large amounts”.

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Mouthwashes

 Mouthwashes can be used for therapeutic & cosmetic purposes

 Therapeutic mouthwashes can be formulated to reduce plaque, gingivitis, dental
carries.
 Cosmetic mouthwashes may be formulated to reduce bad breath

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Mouthwashes …
Mouthwashes generally contain 4 groups of excipients
1. Alcohols:
 It enhances the flavor, provides sharpness to the taste,
 Aids in masking the unpleasant taste of active ingredients.
 Functions as a solubilizing agent for some flavoring agents, and may a preservative.
2. Humectants: such as glycerin and sorbitol
 Increase the viscosity of the preparation
 Enhance the sweetness of the product
 Improve the preservative qualities of the product

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Mouthwashes …
3. Surfactants
 Non ionic and anionic surfactants
 Aid in the solubilization of flavors.
 Cationic surfactants such as cetylpyridinium chloride
 Are used for their antimicrobial properties, but these tend to impart a bitter taste.
4. Flavours
 Are used to overcome disagreeable tastes.
 e.gs of principal flavoring agents are peppermint, cinnamon, menthol...
5.Colouring agents

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Topical solutions
 Liniments:
 Definition:
 Alcoholic or oleaginous solutions or emulsions of various medicinal substances
intended for external application to the skin, generally with rubbing.
 Liniments are liquid preparations intended for external application.
 Types:
1. Alcoholic liniment-
 Used as rubefacient ( induce mild irritation with reddening of the skin),
counterirritant, mildly astringent and penetrating effect.
2.Oily liniments- are milder in action and less irritating to the skin than the
alcoholic,
 Used as protective coating and use as rubefacient for muscular pain
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Liniments…
 Two types of vehicle are used for liniments that are solutions.
 High concentration of alcohol (as in Soap Liniment)
 Oil (as in Camphor Liniment).
 Although alcohol is primarily used as a solvent,
 It aids penetration of medicaments into the skin and
 It is also potentiates their counter-irritant or rubefacient action.
 Liniments should never be applied to broken skin because
 They would be very irritating, especially if the solvent is alcohol.
 Cool storage is necessary because all Liniments have volatile ingredients.

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Liniments…
 Different Forms by which Liniments  All liniments Must Bear A Label
can occur:-
 Indicating
1) As a emulsion
1. For external use only
2) As a suspension
2. Shake well for emulsion or
3) As a solution suspension
 Methods of Preparation 3. Store in tight containers
 Liniments are prepared in the same 4. Not to be applied to bruises or
manner as broken skin areas
 Solutions,
 Emulsions or
 Suspensions.
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Liniments…
 Are liquid or semi liquid preparations  Application: While
 Meant for external application to  Liniments are stimulating
the skin. preparations

 The medium employed can be aqueous  Are applied vigorously,

or alcoholic or suspensions in aqueous  Lotions are usually smoothing and
medium. are applied gently by dabbing.
 About half of the official lotions are  Uses:
solutions.  Cooling,
 Smoothing or
 Protective action to the skin.

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Liniments…

 Formulation:
 Medicaments
 Vehicles: Purified water, alcohol and Isopropyl alcohol
 Co-solvents: Glycerin, propylene glycol, poly ethylene glycol
 Flavoring agents: Rose water
 Preservatives: Methyl paraben, propyl paraben
 If lotions are alcoholic or hydro-alcoholic preservatives are not required
 If lotions are aqueous preservatives are incorporated

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Liniments…

 Categories of medicaments used in lotions:

1. Antiseptics (zinc oxide, precipitated sulphur)
2. Astringents (calamine, zinc oxide, zinc sulphate, precipitated Sulphur)
3. Germicides.

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Liniments…
 Method of preparation  Label
 Simple solution method  For external use only
 Storage:  Shake well before use
 Lotions should be stored in a cool place,  Sore in cool place
away from flame or heat
 Direction: Apply without rubbing or
 Because of the presence of highly
friction.
 Volatile and inflammable solvents like
alcohol (95%) or industrial methylated
spirit.

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Paints
 All the official paints are solutions.
 Water is the solvent for Crystal Violet Paint, But organic solvents, alone or
mixed with water, are used for other paints.
 Dyes are often light, fine powders that easily float into the air if carelessly
handled.
 Can be applied onto Skin and mucous membranes.
 All paints cannot be used for application onto mucous membrane
 All paints, except throat paints are labeled 'For external use only'.
 Skin paints:
 Contain volatile solvent that evaporates quickly to leave a dry resinous film of
medicament.
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Paints….
 Throat paints:
 Are viscous due to a high content of glycerol,
 Designed to prolong contact of the medicament with the affected site.
 Glycerine is commonly used as a vehicle.
 Are applied to the affected part with the help of cotton plug,
 They should be applied as such, without dilution with water.
 Medicaments used:
 Astrigents: Tannic acid, Boric acid
 Antiseptics: Iodine, Crystal violet
 Anti-infectives: Phenol
 Analgesics: Clove oil, Potassium Permanganate
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Paints
Examples:
Throat paints….  Crystal violet paint
Components:  Compound iodine throat paint
 Medicaments  Label
 For external use only
 Glycerin
 Store in a cool place
 Sweetening agents
 Shake well before use
 Flavoring agents
 Not to be swallowed
 Stabilizers
 Keep the container tightly closed
 Preservatives
Storage:
Method of preparation:
 In a cool and dark place.
 Simple solution.
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Collodions
 Are liquid preparations containing pyroxylin (soluble gun cotton, collodion
cotton),
 Dissolved in a solvent mixture usually composed of ethyl ether and ethanol with
or without medicinal substance.
 When the ether and ethanol have evaporated, leave a film of pyroxylin on the
surface.
 Intended for external use only.
 Applied to the skin
 By means of a soft brush or other suitable applicator.
 Uses Of Collodion
1. As a protective coating to the skin.
2. As medication where a thin layer of the medication is firmly placed against the skin.
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Collodions
 Salicylic Acid Collodion  Flexible collodion
 Official medicated collodion  A non-medicated collodion and used
as a vehicle for medicated collodions.
 10% solution of salicylic acid in
flexible collodion.  Is prepared by adding 2% camphor
and 3% castor oil to collodion.
 It is used for its keratolytic effects,
especially in the removal of corns from  The castor oil renders the product
the toes. flexible,
 Permitting its comfortable use over skin
areas that are normally moved, such as
joints, fingers, and toes.
 The camphor makes the product
waterproof.

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Collodions….
 Storage:
Stored in small light-resistant, well closed containers at a temperature not exceeding 20 0C.
 Label:
 For external use only
 Store in a cool place
 Highly Inflammable
 Keep away from naked flames

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Solutions instilled into body cavities

 Enemas  Types of Enema:

 Enemas are also known as Clyster 1. Evacuation Enemas- employed to
promote evacuation.
 Are preparations intended for
introducing in the rectum for 2. Retention Enemas- For local action
in the rectum
 Cleansing, therapeutic or
diagnostic purposes. a. Nutritive Enema - supply nutrient
to the patient
 Given at body temperature b. Medicated Enema - supply
 Injected slowly with enema syringe. medication for systemic effect
3. Diagnostic Enema - BaSO4 enema

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Douches
 A douche is an aqueous solutions which is directed into body cavity.
 It functions as a cleansing or antiseptic
 Usually directed using Bulb syringe.
 Types of douches
 Eye douches
 Are used to remove foreign particles and discharges from the eyes.
 Is directed gently at an oblique angle and
 Is allowed to run from the inner to the outer corner of the eye.
 Pharyngeal douches
 Are used to prepare the interior of the throat for an operation and to cleanse it in
supportive conditions.
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Douches
 Similarly, there are nasal and vaginal douches.
 Douches most frequently dispensed in the form of a powder
 Directions for dissolving in a specified quantity of water.
 Example: Dobell’s Solution Tablets (Compound Sodium Borate Solution NF)
 Used as nasal or pharyngeal douches.

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Douches….
 Among the components of douche powders are the following:
 Boric acid or sodium borate
 Astringents, e.g. potassium, ammonium, zinc sulfate
 Antimicrobials, e.g. oxyquinoline sulfate, povidone iodine
 Quaternary ammonium compounds, e.g. benzethonium chloride
 Detergents e.g., sodium lauryl sulfate
 Oxidizing agents, e.g., sodium perborate
 Salts, e.g., sodium citrate, sodium chloride
 Aromatics, e.g. menthol, thymol, eucalyptol, methyl salicylate, phenol

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Nasal Solutions
 Solutions are usually aqueous nasal solutions designed to be administered to the
nasal passages in drops or sprays.
 Nasal drops spread more extensively than the spray.
 Three drops cover most of the walls of the nasal cavity, with the patient in a supine
position and head tilted back and turned left and right
 The adult nasal cavity has about a 20 ml capacity with a large surface area (about
180 cm2) for drug absorption afforded.
 Another advantage nasal delivery is to avoids first-pass metabolism by the liver.
 The nasal tissue is highly vascularized making it an attractive site for rapid and
efficient systemic absorption.
 For some peptides and small molecular compounds, intranasal bioavailability has
been comparable to that of injections.

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Nasal Solutions
 Commercial nasal preparations include antibiotics, antihistamines and drugs for
asthma prophylaxis.
 Nasal solutions are prepared are similar in many respects to nasal secretions, so that
normal ciliary action is maintained.
 Aqueous nasal solutions usually are isotonic and slightly buffered to maintain a pH
of 5.5 to 6.5.
 Nasal sprays are solutions of drugs in aqueous vehicles & are applied to the
mucous membrane of the nose by means of an atomizer or nebulizer.
 The spray device should produce relatively coarse droplets if the action of the drug
is to be restricted to the upper respiratory tract.
 Fine droplets tend to penetrate further into the respiratory tract than is desirable.
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Otic Solutions
 Otic solutions occasionally are referred to as ear or aural preparations.
 Ear preparations are usually placed in the ear canal by drops for
 The removal of excessive cerumen (ear wax) or
 The treatment of ear infections, inflammation, or pain.
 The main classes of drugs used for topical administration to the ear include
 Local anesthetics, e.g. benzocaine
 Antibiotics e.g. neomycin
 Anti-inflammatory, e.g hydrocortisone

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Otic Solutions
 These preparations include the main types of solvents used glycerin, propylene
glycol or water.
 The viscous glycerin or PG vehicle permits the drug to remain in the ear for a long
time
 Viscous liquids like glycerin or propylene glycol either
 Are used alone or in combination with a surfactant
 To aid in the removal of ear wax
 For aqueous preparations to act,
 It is necessary for the patient to remain on his side for a few minutes so the drops do not
run out of the ear.

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Parenteral Solutions

 “Parenteral” comes from two Greek words,

 “Para”(outside)
 “Enteron” (intestine)
 Meaning “Beside the intestine”.
 Injected directly in to body
 It by passes alimentary canal

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 Parenteral solutions…

 Advantages:
 Disadvantages:
 Fastest method of delivering drugs Traumatic injury from the insertion of
(quick onset of action) needle; pain at site
 Provides higher concentration of drug to Potential for introducing toxic
bloodstream or tissues agents, microbes and pyrogens
Impossible to retrieve if adverse
 Vomiting and unconscious patients can
reactions occurs
take
Correct syringe, needle, and
 Can provide fluids, electrolytes and
technique should be used
nutrients
Trained personnel required
 Drug action can be prolonged by Necessity of aseptic condition in
modifying the formulation production, compounding and
 Drugs with poor absorption or administration
instability in GIT Expensive
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Parenteral solutions…
 Routes of administration:
 Intravenous (IV) Vein Muscle
 Intramuscular (IM) Under the skin
 Subcutaneous (SC) Into the skin
 Intradermal (ID)

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 Parenteral solutions
Necessities for parenteral preparations:
 Sterility  Do not use coloring agents
 Pyrogen-free  Prepared under aseptic
 Free from particulate matter conditions
 Clarity  Special clothing (gowns, masks, hair
 Stability net, gloves).

 Chemical purity  Laminar flow hoods placed in

 Iso-tonicity special rooms

 Solvents and vehicles used must meet special  Special and high quality
packaging
purity and other standards.

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Parenteral solutions
 Classification based on volume:

Parenteral Products (based on volume)

Small Volume Parenterals Large Volume Parenterals

 Electrolytes
 Pharmaceutical products  Carbohydrates
 Biological products  Nutritional Solutions
Proteins
 Radiopharmaceutical products
Lipid Emulsions
 Liposomes and lipid products  Peritoneal Dialysis
 Irrigating Solutions
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Parenteral solutions
 Classification….

Parameter SVP LVP

Volume 100 and less 101-1000 ml
Routes IV, IM, SC IV-LVP, Non IV-LVP
Dosage unit Single or multiple dose Single dose
Technique Vein puncture Venoclysis
Preservative Used Not used
Buffer Used Not used
Formulation Solution, suspension, emulsion Solution and O/W emulsion
Isotonicity Not essential Must
Example furosemide injection Dextrose 40%,NS,DNS and RL
Oxytocin injection
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Parenteral solutions
Classification based on formulation:
Parenteral Formulations
(Dosage Forms)

Solutions Emulsions Suspensions

Injectable
emulsion
Aqueous Oil-based Aqueous Oil-based

Ready to Powders for Powders for

use reconstitution
Ready to use
reconstitution
 Injection  For injection  Injectable  For injectable
suspension suspension
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Parenteral solutions…
 Injection: are liquid preparations that are substances or solutions, E.g. Insulin
injection
 For injection solution: dry solids that upon addition of suitable vehicles yield
solutions, E.g. Cefuroxime for injection, USP
 Injectable emulsion: liquid preparation of drug substance dissolved or dispersed
in a suitable emulsion medium, E.g. Propofol, USP
 Injectable suspension: liquidpreparation of solid suspended in a suitable liquid
medium. E.g. Methyl Prednisolone Acetate Suspension, USP
 For injectable suspension: dry solid that upon addition of a suitable vehicle
yields injectable suspensions. E.g. Imipenem/Cilastatin Injectable Suspension,
USP

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Parenteral solutions…

• Formulation of parenteral solutions:  Preservatives

 Active drug  Buffers
 Solvents (co-solvents) and Vehicles  Tonicity adjusters
 Adjuvants  Antioxidants
 Surfactants  Chelating agents
 Polymers  Inert gases

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Parenteral solutions…
 Vehicles:
 Solvents & vehicles must meet special purity & other standard to assure
sterility, stability and safety.
 Vehicle used should be:
 Pharmacologically inert,
 Non toxic and compatible with blood,
 Maintain solubility of the drug,
 Be physically and chemically stable
 Does not affect the pH.
 Must be pyrogen free.
 No particulate mater.
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Parenteral solutions…
 Aqueous vehicles:
 Water for injection, USP: is intended for use in the preparation of parenteral
solutions and in the preparation of some bulk pharmaceutical chemicals (in the
large-scale manufacturer of injections).
 It must be protected from microbial contamination.
 Sterile water for injection, USP
 It is prepared from water for injection that is sterilized and suitably packaged
 It is packaged in single-dose containers not larger than 1L
 It contains no antimicrobial agent or other added substance.
 It is used as diluents for parenteral products

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Parenteral solutions…
 Bacteriostatic water for injection, USP:
 Is sterile water for injection which contain one or more suitable antimicrobial
agents.
 It is intended to be used as diluent for parenteral products.
 It is packaged in single or multiple-dose containers (vials), not larger than 30 ml
size
 Sodium chloride injection, USP
 Is a sterile isotonic solution of sodium chloride in water for injection
 May be used as a sterile vehicle in solutions or suspensions of drugs for parenteral
administration
 Contain no antimicrobial agents.

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Parenteral solutions…
 Bacteriostatic Sodium chloride injection, USP
 Is a sterile isotonic solution of sodium chloride in water for injection.
 Contains one or more suitable antimicrobial agents.
 Ringer’s injection, USP
 Is a sterile solution containing NaCl, KCl, and CaCl2 in water for injection.
 The three agents are present in concentrations similar to those of physiological
fluids.
 Used as a vehicle and as an electrolyte replenisher and plasma volume expander.

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Parenteral solutions…

 Non-aqueous vehicles
 Are sometimes used when there are limited water solubility of drugs or
susceptibility to hydrolysis.
 Fixed vegetable oils like corn oil, cottonseed oil, peanut oil, and sesame oil
 But not mineral oil or paraffin b/c not absorbed by body tissues.
 Alcohol;PEG, glycerol, propyl glycol,

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Parenteral solutions…

 Surfactants:
 Enhance drug solubility
 May be incorporated to aqueous or oil-based vehicles
 Examples: Non ionic surfactants (tweens, poloxamers)
 Polymers:
 Hydrophilic polymers to enhance drug solubility by complexation
 Example: Polyvinyl alcohol

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 Preservatives:
 As a bacteriostatic  Examples:
 To inhibit any microbes accidentally  Benzyl alcohol (0.9% to 1.5%)
introduced while doses are being  Methylparaben (0.18% to 0.2%)
withdrawn.
 Propylparaben (0.02%)
 A must in multiple dose containers unless
the drug itself is bacteriostatic  Benzalkonium chloride (0.01% to 0.02%)-
in ophthalmic dosage forms
 As adjuncts in aseptic filling and in
intermittent heat sterilization  Thiomersal (0.001% to 0.01%)

 Not permitted in single doses > 15 ml  Phenolic compounds: Phenol (0.25-0.5%

w/v), Chlorocresol (0.1-0.3% w/v)
 Not for routes reaching cerebrospinal fluid
or inter-ocular.
 Not for oil-based parenteral products (due
to the low water activity of this medium)
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Parenteral solutions…

 Buffers:
 Parenteral preparations should not vary significantly form physiological pH (about 7.4)
 Acidic or alkaline solutions may be needed to Solubilize or stabilize drugs.

pH Buffer system Concentration

3.5-5.7 Acetic acid-acetate 1.0-2.0

2.5-6.0 Citric acid-citrate 1.0-5.0
6.0-8.2 Phosphoric acid-phosphate 0.8-2.0
8.2-10.2 Glutamic acid-glutamate 1-2

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Parenteral solutions…
 Tonicity adjusters:
 Can be:
 Electrolytes: NaCl
 Non-electrolytes: Glucose, mannitol, Glycerine
 An isotonic solution is one that exhibits the same effective osmotic pressure as
blood serum.
 Example of isotonic: Dextrose injection 5% and NaCl injection 0.9%
 Hypotonic Solution: is a solution of lower osmotic pressure than that of a body
fluid.
 Adjusted to isotonicity using Sodium chloride, Glucose, Mannitol
 Hypertonic solutions: the solutions having a higher osmotic pressure than that of a
body fluid.
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Parenteral solutions…

 Antioxidants:
 Oxidative degradation of drug in solution is mediated either
 By molecular oxygen or
 By free redicals and can be catalyzed by metals, heat, light and hydrogen ions.

 Water soluble Oil soluble:

 Sulfurous acid salts  Propyl gallate
 Ascorbic acid isomers  Butylated hydroxyanisole
 Thiol derivatives  Ascorbyl palmitate
 α-Tocopherol

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Parenteral solutions…
 Chelating agents:
 Inert Gas
 Sequester heavy metals
 Boiling the water
 To prevent the catalysis of oxidation
reaction.  Displacing the air in the solution
with nitrogen.
 Examples:
 Purging container N2 or CO2 before
Ethylenediamine tetra acetic acid
filling.
Citric acid and
 Topping off container with the gas
tartaric acid
after sealing
 Use glass-sealed ampoules

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Parenteral solutions…
 Manufacturing Steps in Parenteral Solutions:
Heat sensitive APIs Heat stable APIs
Cleaning of containers, Cleaning of containers, closures
closures and equipments and equipment's

Collection of materials Collection of materials

Preparation of parenteral products

Preparation of parenteral products
Filtration
Aseptic filtration
Filling
Aseptic filling
Sealing
Aseptic sealing Sterility,
Pyrogen, Sterilization
Evaluation Clarity, Leak
test, Assay Evaluation
Labelling and Packaging
Labelling and Packaging

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Parenteral solutions…
 Parenteral packaging systems:
 Injectable formulations are packaged into containersmade of glass or plastic.
 Container systems include ampoules, vials, syringes, cartridges, bottles, and bags:
 Ampoules are all glass, whereas bags are all plastic.
 The other containers can be composed of glass or plastic and must include rubber
materials, such as
 rubber stoppers for vials and bottles and
 rubber plungers and rubber seals for syringes and cartridges.
 Irrigation solutions
 Are packaged in glass bottles with aluminum screw caps.
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Parenteral solutions…
 Glass:  Plastic:
 Is employed as the container material of  Plastic containers can also be used
choice for most Small Volume
Parenterals (SVP).  But they face the following
problems:
 The USP provides a classification of
glass:  Permeation
1. Type I, a borosilicate glass;  Sorption
2. Type II, a soda-lime treated glass;  Leaching
3. Type III, a soda-lime glass; and  Softening
4. Non-parenteral glass: a soda-lime
glass not suitable for containers for
parenterals.
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 Ampoules  They are also used for single dose SVPs.
 Sealed glass containers  A 5 micron filter needle should be used
when drawing the contents
 With an elongated neck that must be
broken off
 Most are weakened around the neck
for easy breaking
 Sealed after filling single dose of
drug /water.
 Most commonly used for supplying
WFI.

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 Parenteral solutions…

Vials:
 Drugs are packaged in vials either as liquids or powders
 Made of glass or plastic
 Are sealed with a rubber stopper
 A needle is needed to add contents to or withdraw from vials
 May be designed for single or multi- dose use
 Multi-dose vials contain a preservative to inhibit bacterial contamination
 Product is easier to remove from vials than form ampoules

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Parenteral solutions…
 Comparison:
Ampoules Vials

 Single dose  Single / multi dose

 No Preservatives  Preservative Not
 Hermetically sealed (air tight) hermetic
Protection from air or humidity  Air /humidity may permeate
 Drugs more stable  Drugs less stable
 Difficult opening Risk of  Easy opening No risk of
injury injury
 Risk of glass contamination  No risk of contamination
 Container is not reusable  Vials are reusable

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Parenteral solutions…
 Closures: Problems associated with rubber
 To provide closure for closures are:

 Multiple dose vials,  Incompatibility

 IV fluid bottles,  Chemical instability

 Plugs for disposable syringes and  Physical instability

 Bulbs for ophthalmic pipettes, Characteristics of good pharma

rubbers:
 Rubber closure is material of choice.
 Good ageing qualities
 Satisfactory hardness and elasticity
 Resistance to sterilization conditions
 Impermeable to moisture and air
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Parenteral solutions…
 Pre-filled syringes:
 Single-dose medicine filled in syringe with fixed needle.
 Plastics / glass sometime
 Labeled properly.
 Emergency drugs are available right away.
 Ease of administration (less steps involved) .
 Self administration is possible.
 Reduction of medication error (right dose always)
 Reduction of contamination (Assurance of sterility).
 Less overfill required (economical for biopharmaceuticals)
 Good control of controlled drugs (e.g. narcotics).

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Parenteral solutions…
 Glass/Plastic Bottles & Plastic Bags:
 They are used for Large volume parenteral
 For IV administration.
 For the intermittent or continuous infusion of fluids or drugs.
 Need special administration devices to permit drug administration.

Cannula Saline Set

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Parenteral solutions…
 Labelling:
 Name and concentration of active substances
 Name and concentration of any added antimicrobial preservatives
 Route of administration
 Shelf- life
 Batch number
 Storage pre-cautions
 Directions for use

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 Thank You!!!
Q???

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