Lecture 10 - Ointments, Creams, and Gels

Ointments, creams, and gels are used for which type of preparations

Dermatological

Ophthalmic

Nasal

Rectal

Vaginal

Lotions are used where

Hard to reach areas (intertriginous)

Creams are used where

On moist or weeping lesions

What is another phrase for “levigating agent”?

Softening agent

Storage requirement common for ointments

Store in a cool dry place

When the fusion process is conducted, the substance with the highest melting point is melted first. T/F

T

Creams

Opaque, soft solids, or thick liquids, intended for external application, contains api that is dissolved and suspended in water-soluble cream base

Creams have a pseudo-plastic flow. T/F

T

The occlusive dressing provides a protective barrier in the oleaginous base. T/F.

T

Absorption bases

Are water insoluble, but can absorb water / anhydrous, oily

• ex.) aquaphor, aquabase

Emulsions base / water-in-oil

Water insoluble / can absorb water / not washable / contains water

Emulsion bases / Oil-in-water

Water insoluble / water washable / can absorb water / contains water (ex. Unbiase, Dermabase)

Gels

Dispersion of small or large molecules in aqueous liquid vehicle, jelly-like, considered an “interlacing network”

Single phase gels

Uniform macromolecule dispersement through a liquid with no apparent boundaries between dispersed and liquid.

Which type of agents are usually found in single phase gels?

Organics

Two phase gel

Gel mass consisting of small floccules that are distinct.

Which compound type are usually found in two phase gels

Inorganics

Components of a gel

Gelling agent

Water

Cosolvents

Preservatives

Stabilizers

Gelation

Process by which a hot dispersion is cooled and macromolecules lose kinetic energy.

• This cooling creates a dipole-dipole threadlike structure

More gel = more networks = more viscous. T/F

T

Syneresis

The dispersing medium is squeezed out in droplets and the gel shrinks

Imbibition

Taking up of liquid without an increase in volume

Thixotropy

Reversible gel to solution formation. No volume or temp change

Gel types

Carbomer gels

Methylcellulose gels

Starch glycerite

Aluminum hydroxide gel

Possible Applications for gels

Oral

Topical

Intra nasal

Vaginal

Rectal

Packaging requirements for gels

Tight containers

Room or refrigerators, (as directed)

The nasal lining has a _____ blood supply

Rich

Uses of rectal preparations

Anorectal pruritus

Inflammation

Hemorrhoids

Use of vaginal preparations

Anti-invectives

Hormones

PH modifiers

Spermicides

Paste

Thick, stiff ointment, don’t flow at body temperature

• > 20% solids

Lotions

Aqueous, external application, Newtonian flow

• usually referred to as “fluid oil-in-water” or “water-in-oil emulsions”

Plasters

Solid or semi-solid, not spread at room temperature

Cataplasms or Poultices

Wet masses of solid matter used to reduce inflammation and act as a counter irritant.