Topical Medication Flashcards
(100 cards)
What are the main types of bases used in topical treatments?
The main types of bases include ointments, creams, lotions, solutions, gels, pastes, foams, and solids. Each type has different compositions and uses depending on the condition being treated.
What is the role of emulsifiers in topical formulations?
Emulsifiers reduce surface tension between oil and water phases, allowing them to mix into a stable emulsion. However, they can cause irritation or contact allergy.
How is the dosage of topical treatments determined?
Dosage is often measured in fingertip units (FTUs), where one FTU is about 0.5 grams. Specific areas of the body require different amounts (e.g., 3 grams for a leg).
What are ointments primarily composed of?
Ointments are primarily composed of grease or oil and are either water-free or nearly water-free (less than 20% water). Common ingredients include hydrocarbons like paraffin, wool fat, and vegetable oils.
What are the benefits of using ointments?
Ointments form an impermeable layer over the skin, reducing transepidermal water loss, increasing barrier function, softening dry skin, easing itching, and allowing active ingredients to penetrate the skin
What types of skin conditions are ointments most suitable for?
Ointments are suitable for dry skin, eczema, and conditions requiring moisture retention and prevention from frostbite.
What are the disadvantages of using ointments?
Disadvantages include being sticky, difficult to apply on hairy skin, occlusive (which can lead to pomade acne), hard to wash off with water, and potentially trapping bacteria, yeasts, and fungi.
How do non-emulsifying and emulsifying ointments differ?
Non-emulsifying ointments do not penetrate the skin and have only superficial activity. Emulsifying ointments contain some water and can help mix oil and water phases, improving the delivery of active ingredient
What are some common emulsifiers used in ointments?
Common emulsifiers include lanette wax, cetomacrogol wax, beeswax, cetostearyl alcohol, and sodium lauryl sulfate, which help mix oil and water phases in emulsifying ointments.
In what situations might ointments increase the risk of sunburn?
Ointments can increase the risk of sunburn by acting like a magnifier, reflecting and concentrating sunlight on the skin.
How can ointments aid in preventing frostbite?
Ointments can aid in preventing frostbite by forming a protective barrier that retains heat and moisture, protecting the skin from extreme cold.
Why might ointments not be suitable for wet or exudative skin conditions?
Ointments are not suitable for wet or exudative conditions because they are occlusive and do not mix well with skin exudates, potentially worsening the condition.
What are creams composed of?
Creams consist of lipophilic (fat-loving) and hydrophilic (water-loving) phases combined with one or more emulsifiers and preservatives. They have a water content that allows them to rub into the skin easily.
What are the two main types of creams, and how do they differ?
The two main types are oil-in-water (O/W) creams and water-in-oil (W/O) creams. O/W creams have an aqueous outer phase, are washable, and are cosmetically acceptable, while W/O creams have a fatty outer phase and better drug absorption.
What are the advantages of using creams?
Advantages of creams include easy application, cosmetic friendliness, being less or non-occlusive, and serving as a good base for many active ingredients.
What are some disadvantages of using creams?
Disadvantages include the need for preservatives and emulsifiers, potential skin drying, higher cost compared to ointments, and stability problems.
In what situations are oil-in-water creams most suitable?
Oil-in-water creams are suitable for normal or slightly oily skin and for conditions like eczema that are a bit oozing. They leave a thin layer of oil on the skin as the water evaporates, which may be too drying for very dry skin
When are water-in-oil creams preferred?
Water-in-oil creams are preferred for dry skin conditions because they enhance the absorption of active ingredients and are more stable in warm conditions. However, they are less suitable for wet dermatitis and tropical climates due to stability issues.
How do creams differ in their application to different areas of the body?
Creams are preferred in areas like skin folds and flexural areas due to their non-occlusive nature, which reduces the risk of irritation and maceration that can occur with ointments.
Why do creams require preservatives?
Creams require preservatives to prevent microbial growth, as their water content makes them vulnerable to contamination.
What role do emulsifiers play in creams?
Emulsifiers help combine the oil and water phases in creams, creating a stable emulsion that allows the cream to be spread easily and absorbed into the skin.
How can the stability of creams be enhanced?
Stability can be enhanced by adding humectants like glycerol or sorbitol to prevent water evaporation, especially in stored creams. This helps maintain the cream’s consistency and effectiveness over time.
What are lotions?
Lotions are low-viscosity topical preparations consisting of a mixture of oil and water, typically with an emulsifier. They are thinner than creams and ointments, making them easy to spread over large areas.