Skin Therapeutics/Topicals Flashcards
Describe a lotion
Liquid formulation, suspension or solution of medication in water, alcohol or other liquids. If contain alcohol, may sting. Ideal for hair bearing areas eg. Scalp
What are gels?
Thickened aqueous lotions. Semi solids, containing high molecular weight polymers eg. Methylcellulose. Treat scalp, hair bearing areas, face
What are pastes?
Semisolids. Contain finely powdered material. Stiff, greasy, protective, occlusive, hydrating. Often used in cooking, drying, soothing bandages. E.g. Around leaking stoma
What are emollients used for?
Enhance rehydration of epidermis. All dry/scaly conditions esp eczema. Prescribe 300-500mg weekly. Frequent application. Can be used as soap substitute
What is wet wrap therapy?
Used for very dry (xerotic) skin. Can apply to whole body, moisturiser etc pre applied.
What are the modes of action of topical steroids?
Vasoconstrictive, anti-inflammatory, antiproliferative
What can topical steroids do and what are the categories of these with examples?
Reduce inflammation, cause immune suppression.
Mild- Hydrocortisone. Moderate- Modrasone. Potent- Betamethasone. Very Potent- Clobetasol
When are topical steroids used?
Eczema (dermatitis), psoriasis, other non-infective inflammatory dermatoses eg. Lichen planus. Keloid scars (usually intralesional)
What quantities of topical steroids are needed?
1 Application to whole body 20-30g. Fingertip = 1/2g
Name some side effects of topical steroids
Steroid rosacea, perioral dermatitis, fixed telangiectasia, thinning of the skin, purpura and stretch marks. May worsen/mask infections. Systemic absorption. Tachyphylaxis- decrease in response to anti-inflammatory effects. Rebound flare of disease (esp psoriasis)
Describe antiseptics and list some examples
Have bacteriostatic or bactericidal effects e.g. Povidone iodine (Betadine) skin cleanser, chlorhexidine (Hibitane, Savlon), Triclosan (Aquasept, Sterzac), Hydrogen peroxide (Crystacide)
Describe some clinical uses of antiseptics
Recurrent infections, antibiotic resistance, wound irrigation. E.g. Potassium permanganate rinse/soak use in acute exudative eczema, pompholyx
Name some antipruritics
Menthol- added to calamine &other lotions & creams to impart cooling sensation.
Capsaicin- from red chilli peppers - depletes substance P at nerve endings and reduces neurotransmission, effect gradually builds. Camphor/phenol-for pruritis ani. Crotamiton e.g. eurax cream
What are keratolytics used for?
Used to soften keratin; viral warts, hyperkeratotic eczema and psoriasis, corns and calluses, to remove keratin plaques in scalp
Describe the treatment of warts
Mechanical paring plus : keratolytics (e.g. Salicyclic acid), formaldehyde, glutaraldehyde, silver nitrate, cryotherapy (usually liquid N), podophyllin (genital warts)
Name some topical psoriasis treatments
Emollients and choice of coal tar, vitD analogue, keratolytic, topical steroid, dithranol
Describe an ointment
Semisolid grease/oil (soft paraffin), no preservative. Occlusive/emollient.
Describe a cream
Semisolid emulsion of oil in water-contains emulsifier & preservative. High water content
What topical antibiotics are used in acne?
Clindamycin, erythromycin, tetracycline
What topical antibiotics are used in rosacea?
Metronidazole
What topical antibiotics are used in impetigo?
Mupirocin, fusidic acid
What treatment is used in infected eczema?
Combined corticosteroid/antibacterial (short term)
What type of antivirals would be used in Herpes simplex, eczema herpeticum and herpes zoster?
Topical, oral, oral
What topical antifungals would be used in candida?
Antiyeast e.g. nystatin, clotrimazole
