Ointments Creams and Gels Dr J Domenech INTRODUCTION

Ointments, Creams, and Gels Dr. J. Domenech

INTRODUCTION Topicals • Preparations applied to the skin either for their physical effects or for the specific effect of a medicinal agent • Protectants, lubricants, emollients, drying agents, astringents Transdermals • Designed to support the passage of drug substances from the surface of the skin, through its various layers, and even into the systemic circulation

INTRODUCTION Functions of Dermatologicals • Protect injured areas from the environment • Provide for skin hydration (emollient) • Vehicle for medication transport Drug Penetration Is Dependent Upon: • Amount of pressure and vigor of rubbing • Surface area covered • Condition of the skin • Base used • Occlusive dressing use Application Areas for Dermatologicals LOTIONS Intertriginous areas CREAMS Moist, weeping lesions OINTMENTS Dry, scaly lesions

Ointments • Semisolid preparations intended for external application to the skin or mucous membranes. • Semisolid plastic flow characteristics • Definite yield value • Resistance to flow drops as application continues

Ointments Ointment Bases Preparation of Ointments • Oleaginous Bases • Absorption Bases • Water-Removable Bases • Water-Soluble Bases • Incorporation • Fusion Compendial Requirements for Ointments • Microbial Content • Minimum Fill • Packaging, Storage, and Labeling • Additional Standards

Ointments Oleaginous Bases • Water insoluble • Not water washable • Can’t absorb water • Oily, occlusive, lack cosmetic appeal Examples: • Hydrocarbons (mineral oils, petrolatums, paraffins, waxes) • Animal fats/vegetable oils (castor oil, cottonseed oil, olive oil) • Synthetic esters (glyceryl monostearate, butyl stearate, isopropyl lanolate, stearyl alcohol) • WHITE PETROLATUM • WHITE OINTMENT Absorption Bases • Water insoluble • Not water washable • Can absorb water • Anhydrous • Oily, occlusive, lacks cosmetic appeal Examples: • Hydrophilic petrolatum • Aquaphor • Aquabase

Ointments Emulsion Base Water-in-Oil • Water insoluble • Not water washable • Can absorb water • Contains water Emulsion Bases Oil-in-Water • Water insoluble • Water washable • Can absorb water • Contains water Examples: • Cold Cream (Petrolatum-Rose Water Ointment) • Lanolin • Nivea • Eucerin Examples: • Hydrophilic Ointment • Velvachol • Unibase • Dermabase • Vanicream • Acid Mantle

Ointments Humectants • Glycerin • Propylene glycol • Sorbitol 70% Water-Soluble Bases • Water soluble • Water washable • Can absorb water • Anhydrous or hydrous • All water soluble, no oil phase Example: • Polyethylene Glycol Ointment • Biozyme Ointment, Desenex Ointment, Whitfields Ointment • Veegum 10% Dermatological base • Veegum 5% Thixotropic lotion

Ointments Selection of the Appropriate Base • Release rate • Topical or percutaneous drug absorption • Occlusion • Stability of drug • Effect of drug on ointment base • Easily removable? • Characteristics of surface for application Ointment Preparation • Ointment Slab/Pill Tile • Mortar/Pestle • Ointment Mill • Fusion üHeat highest melting point material first üWater phase a few degrees higher üW/O: add water slowly üO/W: add oil slowly Incorporation • Mortar and pestle • Pill tile and spatula • Ointment mill • Unguator • Incorporation of solids • Incorporation of liquid

Ointments Ointment Packaging • Jars: Glass, Plastic üDo not pour in while hot! • Disp. Jars: Plastic • Tubes: Plastic, tin, aluminum • Syringes: Individually dosed, good protection of the product Labeling and Storage • Labeling üProtect with tape üDual labels üCreativity often required • Storage üStore in a cool place

Creams • Opaque, soft solids, or thick liquids intended for external application. • Semisolid, pseudoplastic flow • Very little yield value • Won’t flow under force of gravity but small force will initiate flow • Viscous liquids or semisolid emulsions of either the O/W type or the W/O type • Term “cream” is most frequently applied to soft, cosmetically acceptable types of preparations.

Gels • Semisolid systems consisting of dispersions of small or large molecules in an aqueous liquid vehicle rendered jelly-like through the addition of a gelling agent • A semirigid system in which the movement of the dispersing medium is restricted by an interlacing network of particles or solvated macromolecules of the dispersed phase

Gels Types of Gels • Single Phase üGels in which the macromolecules are uniformly distributed throughout a liquid with no apparent boundaries between the dispersed macromolecules and the liquid üUsually involve organics • Two Phase üWhen the gel mass consists of floccules of small distinct particles üUsually involve inorganics

Gels Gel Composition • Gelling agent • Water • Cosolvents • Preservatives • Stabilizers Kinds of Gels Gelation • As a hot, colloidal dispersion of gelatin cools, the gelatin macromolecules lose kinetic energy. • With a reduction of kinetic energy or thermal agitation. • Gelatin, agar, pectin, Irish moss, pectin, tragacanth form gels by this mechanism. • Hydrogels üSilica, bentonite, pectin, sodium alginate, methylcellulose, alumina • Organic Gels üContain an organic liquid (e. g. , Plastibase) • Carbomer Gels üAqueous dispersion neutralized with sodium hydroxide or triethanolamine • Methylcellulose Gels • Starch Glycerite • Aluminum Hydroxide Gel

Gels Phenomena Associated with Gels • Syneresis - When the interaction between particles of the dispersed phase becomes so great that on standing, the dispersing medium is squeezed out in droplets and the gel shrinks • Swelling -The taking up of liquid by a gel with an increase in volume • Imbibition - The taking up of a certain amount of liquid without a measurable increase in volume • Thixotropy -A reversible gel-sol formation with no change in volume or temperature • Jelene/Plastibase - A combination of mineral oils and heavy hydrocarbon waxes with a MW of about 1300 • Carbomer 934 - A polymer of acrylic acid cross-linked with a polyfunctional agent; recognized as an official emulsifying and suspending agent

Gels Applications • Oral • Topical • Intranasal • Vaginal • Rectal Gelling Agents • Alginic acid • Bentonite • Carbomer • CMC Sod • Colloidal Silicon Dioxide • Veegum • Methylcellulose • Plastibase/Jelene • Poloxamer/Pluronic • Povidone • Propylene Glycol Alginate • Sodium Alginate • Tragacanth

Quality Control • Appearance • Uniformity • Weight/Volume • Viscosity • Clarity • p. H • Others Packaging/Storage/Labeling Stability • Physical Stability - Shrinkage - Separation of liquid from the gel - Discoloration • Microbial Stability • BUD: Unless otherwise documented, 14 days when stored in a refrigerator (USP) • Tight containers • Room or refrigerated temperatures, as appropriate • Prior to use, store in tight containers. Patient Counseling • Proper application • Proper storage • Keep tightly closed

Gels Transdermal Preparations • Pastes • Plasters • Glycerogelatins • Packaging Semisolid Preparations - Filling Ointment Jars - Filling Ointment Tubes Features and Use of Dermatologic Preparations • Ointments • Creams • Gels • Pastes • Plasters • Topical or systemic effect

Gels Features and Use of Ophthalmic Ointments and Gels • Relative short residence time after application • Sterile • Nonirritating • Softening point close to body temperature • Application technique Features and Use of Nasal Ointments and Gels • Primarily local effects but some systemic also • Rich blood supply in nasal lining

Gels Features and Use of Rectal Preparations • Ointments, creams, gels • Perianal area and anal canal • Anorectal pruritus, inflammation, hemorrhoids • Proper instruction for use to patient Features and Use of Vaginal Preparations • Ointments, creams, foams, and gels • Anti-infectives, hormones, p. H modifiers, spermicides

Others Pastes • Thick, stiff ointments that do not ordinarily flow at body temperature, and therefore serve as protective coatings over the areas to which they are applied. Usually >20% solids. • Semisolid, dilatant flow • Definite yield value • Resistance to flow increased with increased force of application Lotions • Aqueous preparations with insoluble material for external application without friction • Fluid preparations, Newtonian flow • No yield value • Flow under gravity • “Lotions” actually also refers to fluid oilin-water and water-in-oil emulsions.

Others Cerates • Semisolid preparations containing a relatively high wax content • Semisolid • High yield point • Not to be directly rubbed onto skin Plasters • Solid or semisolid preparations that cannot be spread at room temperature Cataplasms or Poultices • Wet masses of solid matter applied to the skin to reduce inflammation and act as counterirritants

Prepared By: Cerna, Divina Dipus, Sheenara Rabara, Starette