Topicals Flashcards
State at least FOUR types of ointment bases.
Four from hydrocarbon, fats and fixed oils, silicone, absorption,
emulsifying and water-soluble.
For TWO ointment bases, write a suitable formulation.
Paraffin Ointment BP – HP(3%), WSP(90%), White Beeswax (2%),
(hydrocarbon base) cetostearyl alcohol (5%).
Simple Ointment BP – Wool fat (5%), HP (5%), cetostearyl alcohol (5%),
(absorption base) yellow or WSP (85%).
Emulsifying Ointment BP – emulsifying wax*(30%),WSP (50%),LP (20%)
(emulsifying bases) *cetostearyl alcohol/sodium lauryl sulphate
(Anionic Emulsifying Wax BP)
Macrogol Ointment BP – PEG 4000 (40%), PEG 400 (60%).
(water-soluble base)
Describe the mechanism by which ointments emolliate the skin.
Ointments soften or melt at body temperature, forming an occlusive film
on the surface of the skin. This prevents transepidermal water loss
causing the skin to hydrate.
What is the functions of skin?
protection from pollution, temperature, humidity & radiation.
a protection for internal organs.
- a limiter for the passage of chemicals.
- a stabiliser for blood pressure & temperature.
- a mediator of heat, cold, touch and pain.
- expresses the emotions of fear,anger, embarrassment, and anxiety.
- an indicator of human characteristics such as colour, hair, odour & texture.
What are the three main regions of skin?
Epidermis, Dermis, Subcutaneous tissue
Features of the epidermis
multilayered - thickness varies - palms and soles 0.8mm and eyelids are 6 micrometres
Stratum corneum is the dead , dense and impermeable surface layer
Swells several-fold in water (maceration)
Features of the Dermis
3-5cm thick
Matrix of connective tissue woven from fibrous proteins (collagen, elastin and reticulin)
nerves, blood vessels and lymphatics traverse the matric and skin appendages pierce it
What are the different skin appendages?
Eccrine sweat glands
apocrine Sweat glands
Sebacious glands
Hair follicles
What are skin appendages?
The skin appendages include sweat glands, nails, and the pilosebaceous unit of the skin, comprised of the hair shaft, hair follicle, sebaceous gland, and arrector pili muscle — these appendages derive from a down growth of the epidermis beginning in the third month of fetal life.2
What are eccrine sweat glands?
Produce sweat of pH 4.0-6.8
Secrete drugs,protein, antibodies and antigens
AID HEAT CONTROL
What are Apocrine sweat glands?
Develop at the pilosebacious follicle
Milky or oily secretion contain proteins, lipids, lipoproteins and saccharides
surface bacteria metabolise this (initially) odourless liquid to produce body smells
What are sebacious glands?
Sebacious glands open into hair follicles
they produce sebum from cell disintegration
contain glycerides, fatty acids, cholesterol and its esters, wax esters and squalene
What are hair follicles?
Develop over all skin except lips, palms and soles
What is the problem and treatment for the Stratum Corneum? adv and disadv treatment
give eamples of non proprietary and proprietary
To hydrate the horny layer
To stimulate ‘sloughing’ (keratosis) or exfoliation
Emollients are used because
- Sooth, smooth and hydrate the skin.
- Indicated for all dry or scaling disorders
- As the effects are short-lived, they are applied frequently
- Useful in dry and eczematous disorders.
- Have limited use in the treatment of psoriasis
Non-proprietary: Aqueous Cream BP, White Soft Paraffin BP,
Liquid and White Soft Paraffin Ointment NPF,
Emulsifying Ointment BP, urea* etc.
Proprietary: Neutrogena™, Cetroben™, Ultrabase™, *Neutraplus™
What is the treatment for hyperhydrosis of sweat glands?
Reduce hyperhydrosis of the sweat glands
eg with antiperspirants containing aluminium salts - aluminium chloride hexahydrate 20% alcohol solution (Anhydrol Forte™)
Treatment of acne
Treatment of acne (mild to moderate)
eg topical exfolients such as salicylic acid, benzoyl peroxide,
tretinoin (retinoic acid), isotretinoin and azelaic acid.
- Brevoxil™ is an aqueous cream containing benzoyl peroxide 4%.
topical antibiotics containing erythromycin and clindomycin.
Treatment of fungal diseases?
Treatment of fungal diseases (localised)
eg dermatophytoses of the scalp, body, groin, hand, foot or nail.
- topical imidazoles include clotrimazole, econazole, miconazole, keroconazole and sulconazole (also effective against Candidiasis).
Treatment of male pattern baldness
Treatment of male pattern baldness
eg Finasteride™, Minoxidil™
Treatment of conditions with the epidermus/ dermus
efficient delivery of drug to the receptor
use of ‘pro-drug’ (release active when at target receptor)
Antiinflammatories - steroidal and non-steroidal (NSAIDs). Non-proprietary: Ketoprofen gel, Piroxicam gel. Proprietary: Oruvail™ gel, Feldene™ gel, Fenbid™ (ibuprofen), Voltarol™(diclofenac).
Anaesthetics - relief of local pain (*can cause hypersensitivity). Benzocaine, amethocaine, lignocain.
Antipruritics*- alleviate itching of pruritis in eczema. Calamine (often ineffective), Eurax™(crotamiton), Xepin™ (doxepin hydrochloride 5%).
Antihistamines* - Effective against insect bites & stings (not eczema). Anthisan™(mepyramine), Wasp-Eze™ (antazoline).
UV (PUVA) and - The psoralens/with UV-light mitigate psoriasis.
light (PDT) therapies - Aminolaevulinic acid/with light treats skin cancer.
How to formulate a liquid?
Simple soaks/baths
- an active ingredient in aqueous solution
or suspension.
- gums and gelling agents may vary the consistency.
- Oilatum™ emollient bath additive deposits
a layer of liquid paraffin/wool alcohols
on stratum corneum.
- Oilatum™ Plus contains benzalkonium chloride
and triclosan as parasiticides/antiseptics.
Formulation of ointments?
Greasy, semisolid preparations
- hydrocarbon bases act as emollients and inc hydration of the stratum cornea. Liquid and soft paraffins (VASELINE Vicks VAPOUR RB, WHITE SOFT PARAFFIN AND PETROLEUM JELLY. - fats and fixed oil bases non volatile plant/animal origin - silicone bases , water - absorption bases, water and oil emulsions fatty and water compounds readily absorb water - emulsifying bases - water and oil emulsions - surfactants with fatty alcohols sitosterol high HLB. - water-soluble bases. non greasy easily removed from skin oil and water emulsions
Formulation of liniments and lotions
Liniments
- alcoholic or oily solutions or emulsions.
- do not apply to broken skin. (alcohol will sting)
- massaged into the skin as counterirritants.
- can contain methyl salicylate or camphor. (essential oils)
Lotions
- aqueous solutions/suspensions. - evaporation of water/alcohol cools & soothes the skin. takes away heat from skin - can be dilute O/W emulsions. lotions
Formulation of oily creams?
Oily creams
contain a W/O emulsifying agent
wool fat, wool alcohols, fatty acid sorbitan esters
and their salts (eg calcium).
Formulation of aqueous creams?
Aqueous creams
- contain an O/W emulsifying agent
- emulsifying waxes/alkali salts of fatty acids
- polyethylene glycol derivatives of sorbitan esters.
Give an example of solid/semi-solid, what is it used for? PASTE
Zinc and salicylic acid paste BP (Lassar’s Paste) is a
non-proprietary paste for the treatment of hyperkeratotic skin disorders, warts and calluses, scalp conditions and fungal nail infections.
Contains: zinc oxide (24%), salicylic acid (2%),
starch (24%), white soft paraffin (50%).
Zinc oxide - a mild astringent and topical protectant with some antisceptic action
salicylic acid - exfolient
starch - binder and thickening agent
white soft paraffn - emollient
Give an example of solid/semi-solid, what is it used for? OINTMENT
Emulsifying Ointment BP is a mixture of emulsifying wax – cetostearyl alcohol/sodium lauryl sulphate - (30%),
white soft paraffin (50%) and liquid paraffin (20%).
It is readily miscible in water and forms an ‘emulsifying base’
for many topical preparations. On its own, it is indicated for
all dry or scaling disorders.
cetostearyl alcohol: emollient/ emulsifier/viscosity enhancer.
sodium lauryl sulphate: anionic surfactant/wetting agent skin penetrant/emulsifying agent.
white soft paraffin: emollient
liquid paraffin : emollient
