Pharmaceutical Creams Overview
34 Questions
0 Views

Pharmaceutical Creams Overview

Created by
@HandsomeCalculus

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a key characteristic of creams that makes them susceptible to microbial growth?

  • Emulsification
  • Presence of water (correct)
  • Low pH
  • High viscosity

    • Which type of cream is known for its ability to promote prolonged contact at the site of application?

  • Lotions
  • Ointments
  • Creams (correct)
  • Gels

    • What is a disadvantage of using creams compared to ointments?

  • More washable
  • Higher risk of contamination (correct)
  • Less irritating to the skin
  • Faster drying on application

    • What is another name for oil-in-water (o/w) creams?

    <p>Aqueous creams</p> Signup and view all the answers

    Which emulsifying agents are commonly used to produce water-in-oil (w/o) creams?

    <p>Natural emulsifiers</p> Signup and view all the answers

    What is a characteristic of O/W creams according to the miscibility test?

    <p>Miscible with water</p> Signup and view all the answers

    Which of the following oils is NOT mentioned as a source for vegetable oils?

    <p>Sunflower</p> Signup and view all the answers

    What type of cream is described as providing good emollient properties but is not readily washable by water?

    <p>Cold cream</p> Signup and view all the answers

    Which type of oil is primarily described as chemically inert and occlusive?

    <p>Mineral oils (paraffins)</p> Signup and view all the answers

    What is true about the droplets of O/W emulsions when observed under UV radiation?

    <p>They fluoresce</p> Signup and view all the answers

    Which of the following statements regarding mineral oils is correct?

    <p>They are primarily used for their occlusive nature.</p> Signup and view all the answers

    What type of cream typically has a continuous phase that fluoresces?

    <p>W/O cream</p> Signup and view all the answers

    In which test do O/W creams demonstrate their electrical conduction properties?

    <p>Conductivity measurement</p> Signup and view all the answers

    Why is it necessary to always make an excess when compounding creams?

    <p>To account for potential losses during the compounding process</p> Signup and view all the answers

    What is the recommended extra amount to prepare when compounding cream?

    <p>10% more than the required amount</p> Signup and view all the answers

    What should be checked before preparing the fatty base for cream compounding?

    <p>The melting point of the fatty base</p> Signup and view all the answers

    At what temperature should the fatty base be cooled before mixing other ingredients?

    <p>60ºC</p> Signup and view all the answers

    Why might the temperature of the aqueous phase be adjusted to a few degrees higher than the oily phase?

    <p>To compensate for the cooling rate of the aqueous phase</p> Signup and view all the answers

    What is the concentration range for Butylated Hydroxyanisole as an antioxidant?

    <p>0.02~0.5% w/w</p> Signup and view all the answers

    Which of the following is NOT a recommended humectant for creams?

    <p>Sodium metabisulphite</p> Signup and view all the answers

    What is the primary purpose of levigation in cream compounding?

    <p>To incorporate insoluble coarse powders</p> Signup and view all the answers

    At what temperature range is mixing by fusion typically performed when making ointments?

    <p>60~70°C</p> Signup and view all the answers

    Which term refers to the process of grinding powders to mix them into a base?

    <p>Trituration</p> Signup and view all the answers

    What is the maximum recommended concentration of sodium metabisulphite as an antioxidant?

    <p>1% w/v</p> Signup and view all the answers

    Why is hygiene emphasized in the process of compounding creams?

    <p>To avoid contamination</p> Signup and view all the answers

    Which of the following is involved in the 'doubling up' technique during trituration?

    <p>Incorporating powders into a base</p> Signup and view all the answers

    What is the appropriate temperature to add the disperse phase when making creams?

    <p>60°C</p> Signup and view all the answers

    How should the emulsion be stirred during the preparation of the cream?

    <p>Continuously without incorporating air</p> Signup and view all the answers

    What can be a consequence of hastening the cooling process during cream preparation?

    <p>Poor product consistency</p> Signup and view all the answers

    What is the primary role of the cetrimide in the Dimethicone cream formulation?

    <p>Preservative</p> Signup and view all the answers

    What is the total weight of the oily phase in the Dimethicone cream formula?

    <p>505 g</p> Signup and view all the answers

    What type of cream is being prepared according to the master formula provided?

    <p>Oil-in-water (o/w) cream</p> Signup and view all the answers

    Which ingredient in the formulation serves as a thickening agent?

    <p>Cetostearyl Alcohol</p> Signup and view all the answers

    What should one avoid while stirring the emulsion during cream preparation?

    <p>Incorporating air</p> Signup and view all the answers

    Study Notes

    Creams

    • Viscous semisolid emulsions for external use only
    • Susceptible to microbial growth due to the presence of water
    • Consists of medicaments which can be dissolved or suspended in either oil-in-water or water-in-oil cream base

    Advantages of Creams

    • Prolonged contact at the application site
    • Non-sticky and easily washable
    • Non-irritating on application to the skin
    • Dry the injured area more quickly than ointment

    Disadvantages of Creams

    • Less hydrophobic, hence higher risk of contamination

    Oil-in-water (o/w) Creams

    • Also known as aqueous cream or vanishing cream
    • Produced by synthetic waxes (e.g. macrogol, cetomacrogol)
    • Thin, white, and smooth in consistency
    • Water washable base for rapid absorption and penetration of drugs
    • Examples: aqueous cream, cosmetic creams

    Water-in-oil (w/o) Creams

    • Also known as oily cream
    • Produced by natural emulsifiers (e.g. beeswax, wool fat or wool alcohols)
    • Creamy, white or translucent, and rather stiff
    • Provide good emollient properties; not readily washable by water; gives a cooling sensation
    • Examples: Cold cream

    Distinguishing between O/W and W/O Cream

    • Miscibility Test: O/W creams are miscible with water, while W/O creams are miscible with oil
    • Microscopic Examination: O/W creams have colored droplets after staining with an oil-soluble dye, while W/O have colored backgrounds
    • Microscopic Observation under UV radiation: O/W creams have droplets that fluoresce, while W/O creams have continuous phases that fluoresce
    • Conductivity Measurement: O/W creams are conductors of electricity, while W/O creams are poor conductors

    Oily Vehicles

    • Mineral oils (paraffins): most widely used, complex mixtures of saturated hydrocarbons; occlusive; chemically inert; do not give good skin penetration
    • Vegetable oils: plant sources (e.g. peanut, castor, olive and coconut); occlusive; give good skin penetration
    • Synthetic oils

    Mineral Oils (Paraffins)

    • Commonly used types include soft paraffins, liquid paraffins, and hard paraffins
    • White soft paraffin and yellow soft paraffin are used to thin or thicken products
    • The choice of paraffin depends on the colors of the ingredients

    Vegetable Oils

    • Oxidation can be controlled by adding antioxidants such as:
      • Butylated hydroxyanisole (0.02~0.5% w/w)
      • Butylated hydroxytoluene (0.02~0.5% w/w)
      • Sodium metabisulphite (0.01~1% w/v)
      • Sodium sulphite (0.1% w/v)

    Humectants

    • Hydroscopic materials added to decrease water loss from creams
    • Used at concentrations of 5 - 15%
    • Examples: Glycerol (glycerin), Propylene glycol, Polyethylene glycol 300

    Compounding Creams: Terminologies

    • Mixing by Fusion: Melting together the fatty bases over a water bath before incorporating other ingredients
    • Trituration: Incorporation into the base of finely divided insoluble powders or liquids
    • Levigation: Incorporation of insoluble coarse powders into a base using a shearing force to avoid a gritty product

    General Principles of Compounding Creams

    • Hygiene: Clean all surfaces, spatulas, and equipment with ethanol
    • Always make an excess: Make 2-4g extra to account for loss during the compounding process
    • Check solubility: Determine which ingredients are soluble or miscible in the aqueous phase and which are soluble or miscible in the oily phase
    • Prepare the fatty base: Melt the fatty base in an evaporating dish over a water bath at the lowest possible temperature; cool the fatty base to 60°C; add and mix other ingredients that are soluble/miscible with the oily phase
    • Prepare the aqueous phase: Heat up the aqueous phase to 60°C; dissolve water-soluble ingredients in the aqueous phase
    • Add disperse phase to continuous phase at the same temperature (60°C):
      • For O/W cream: pour oily phase into aqueous phase
      • For W/O cream: pour aqueous phase into oily phase
    • Stir continuously to mix: Stir the resulting emulsion continuously, but not too vigorously, until the product sets.

    Hospital Manufacturing Unit

    • Make sure to follow aseptic techniques and maintain hygiene in the lab

    Dimethicone Cream BPC 1973 (Master Formula)

    • Liquid Paraffin BP (400g) - Oily phase
    • Dimethicone 350 BP (100g) - Miscible with oily phase
    • Cetrimide BP (5g) - Emulsifying wax
    • Cetostearyl Alcohol BP (50g) - Emulsifying wax
    • Chlorocresol (1g) - Preservative
    • Freshly boiled and cooled purified water (444g) - Aqueous phase
    • This is an o/w cream base

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    PHD211 Semi-solid Dosage Forms: Creams PDF

    Description

    Explore the essentials of creams used in pharmaceuticals, including their advantages and disadvantages. This quiz covers the characteristics of oil-in-water and water-in-oil creams, detailing their formulations and uses. Test your knowledge on the various aspects of topical semisolid emulsions.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser