1.1 Creams Flashcards
Definition of cream
Semi-solid dosage forms containing one or more drug substances dissolved or dispersed in a suitable base
There are two types of cream what is it ?
Oil in water (o/w) and
water in oil (w/o)
What is water in oil (w/o) creams
Small droplets of water dispersed in continuous oily phase
What is oil in water (o/w) creams
Small of droplets of oil dispersed in continuous aqueous phase
Two modes of action of cream and meaning
Local and topical (contact with skinwith site action in a period of time)
Localized systemic action (release drug from base and penetrate)
3 Formulation of creams
-active pharmaceutical ingredients (API)
-vehicle
-excipients
Uses of creams
-the barrier to protect skin
-cleansing
-moisturising effect
Ideal Formulations of cream
Non-toxic
Non-harmful
Easy to apply
Incapable of microorganism growth
Free from side effects
Requirements of formulation of cream
-accurate dose
-convenient to apply on skin
-retain quality throughout shelf life
Factors to be considered in Formulations
-physiochemical properties
-choice of vehicle
-categories of excipients
-stability
What about physiochemical properties ?
-oil susceptible to oxidisation (incorporate antioxidants)
-aqueous solutions support microbial growth (incorporate water-soluble preservatives)
Examples of incorporate antioxidants
- BHT (Butylated Hydroxytoluene)
-BHA (Butylated Hydroxynase)
Examples of incorporate water-soluble preservatives
-Methyl
-Propyl paraben
What are excipients ?
Other components other than active ingredient intentionally added to formulation
3 functions of excipients
-aid processing during manufacturing
-assist product identification
improve effectiveness and safety of product during storage or use
5 choices of excipients
-physiological inertness
-physical and chemical stability
-no interference with drug bioavailability
-absence of pathogenic microbial organisms
commercially available at low cost
2 categories of excipients
- Provide essential parts of dosage form
.emulsifiers
.suspending agents
.binders - Prevent degradation of the formulation
.anti-oxidants
.anti-bacterials
.preservatives
What are the physical and chemical properties of excipients ?
-solubility
-hygroscopicity
-hydration capacity
-Bulk density
-microbes
Definition of Hygroscopicity
The capacity of the product to react to the moisture content of the air by absorbing or releasing water vapor
Explain the method of preparation of creams
- Separate the formula components to two…lipid and aqueous
- Both phases are heated to a temperature above the melting point of the highest component
- The phases are mixed and the mixture is stirred until reaching ambient temperature
- Mixing generally is continued during the cooling process to promote uniformity
- Aqueous phase is added to the lipid phase but comparable results have been obtained with the reverse procedure
Examples of cream packing materials
-metals
-plastics
-rubber
-glass
What are containers for creams ?
-wide-mouthed squat jars
-collapsible metal
-flexible plastic tubes
-aluminium tubes
What are the ideal closures of cream packaging ?
-non-reactive
-seal the container
-withstand sterilisation process
-prevent contamination by microorganisms
Packaging and labelling requirements ?
-accuracy
-quality assurance for packaging and labelling
-consistency
–correct language
