Transcript Dermatopharmacology - Learning

Dermatopharmacology
Prof Werner Sinclair
Department of Dermatology
University of the Free State
Outcomes for this Lecture
After this lecture the student should be able to:
Name the most important characteristics and uses of the following antifungals:
Griseofulvin
Terbinafine
Ketoconazole
Fluconazole
Itraconazole
Topical imidazole creams
Discuss the characteristics and uses of the different strengths and formulations of
topical steroids
Name the indications for and most important side-effects of chloroquine
Discuss the indications and use of topical retinoids
Discuss the origin, characteristics of and indications for mupirocin
Discuss the use of tetracyclines in dermatology
Name the uses of the different types of antihistamines (sedating vs non-sedating) in
dermatology
Name the indications for and side-effects of anti-androgens and imiquimod
Drugs To Be Discussed
Antifungals: Griseofulvin
Terbinafin
Fluconazole
Itraconazole
Ketoconazole
Corticosteroids: Topical
Systemic
Chloroquine
1
Drugs To Be Discussed
Retinoids: Topical
Systemic
Benzoyl peroxide
Shampoos
Barriers
Antibiotics: Topical
Systemic
Antivirals: Acyclovir
Podophyllin
Antiscabies: Benzoyl benzoate
2
Drugs To Be Discussed
Antihistamines
Anti-androgens
Imiquimod
3
Antifungals
Griseofulvin
Terbinafin
Fluconazole
Itraconazole
Ketoconazole
Griseofulvin
Only active against dermatophytes
(keratolytic fungi)
Fungistatic
Absorbed with fatty food (milk)
Very safe in children
10 – 20 mg per kg per day
Terbinafin
Only active against dermatophytes
Fungicidal
Tablets and cream
Some severe immunological side-effects
Fluconazole
Broad spectrum
Fungistatic
Convenient once per week dosage
Can be used in neonates
Used for: Candida
Cryptococcus
Itraconazole
Very broad spectrum
Fungistatic
To be taken with meals
Capsules and suspension available
Used for: Any fungal infection
Not better than terbinafin for
dermatophytes
Ketoconazole
Broad spectrum
Fungistatic
To be taken with meals
Tablets, cream and shampoo available
Used for: Seborrheic dermatitis
Pityriasis versicolor
Candidiasis
Side-effects: Liver toxicity
P450 inducer
Imidazole Creams
Variety available
Similar spectra
Little to choose
Price deciding factor
E.g.. Ketoconazole, econazole,
clotrimazole
Corticosteroids
Topical
Systemic
Topical Corticosteroids
3 Strengths
Fluorinated vs Non-fluorinated
Ointments, Creams, Lotions, Shampoos
Topical Corticosteroids
Ointments: More potent
Penetrates deeper
More atrophy
Used for: Dry lesions
Thick lesions
Thick skin
Topical Corticosteroids
Creams: Less potent
Penetrates less
Less atrophy
Used for: Acute, thin lesions
Moist lesions
Thin skin (Face, skin folds)
Topical Corticosteroids
Lotions: Least potent, least atrophy
Used for: Hairy areas (scalp)
Wet lesions (Watery solutions)
Topical Corticosteroids
Shampoos
Clobetasol: Used for psoriasis of the scalp
Systemic Corticosteroids
Prednisone / Prednisolone
Potent, fast acting anti-inflammatory
Cheap
Side-effects: Short term: Almost none
Long term: Severe
Used once daily, in the morning
Chloroquine
Indications: Cutaneous lupus erythematosus
Porphyria cutanea tarda
Side-effects: Corneal deposits (Temporary)
Maculopathy (Permanent)
Other
Retinoids
Topical: Tretinoin
Adapalene
Tazarotene
Comedolytic, anti-inflammatory
Indications: Acne (All forms)
Anti-aging
Other
Retinoids
Systemic: Isotretinoin
Acitretin
Indications: Acne
Psoriasis
Lymphomas
Many others
Side-effects, etc: See acne lecture
Benzoyl peroxide
Comedolytic, antiseptic
Gel / Cream
Superficial, inflammatory acne vulgaris
Shampoos
Ketoconazole: Seborrheic dermatitis
Pityriasis versicolor
(Not for tinea capitis)
Coal tar (LPC): Psoriasis
Povidone iodine (Betadine)
Selenium sulfide (Selsun)
Zinc pyrithione
Barriers
Zinc/Castor oil BP: Nappy rash
Antibiotics
Topical: Mupirocin
Fucidic acid
Gentamycin
Erythromycin
Clindamycin
Systemic: Tetracyclines (oxytetracycline,
doxycycline, minocycline, lymecycline)
Penicillins (amoxycillin, cloxacillin,
amoxycillin-clavulanic acid
Erythromycin
Mupirocin
Manufactured by Pseudomonas bacteria
Broad spectrum
Esp effective against Staphylococci
Ointment and cream
No systemic use
Reserved for short term use
Tetracyclines
Bacteriostatic antibiotics, potent antiinflammatory effects
Used widely in acne, rosacea, bullous diseases
Oxytetracycline: Rosacea
Lymecycline: Drug of choice for acne
Minocycline: Acne in white patients (pigmentation)
Doxycycline: Acne in black patients (phototoxicity)
Penicillins
Cloxacillin, Flucloxacillin, AmoxycillinClavulanic acid: Staph infections
Amoxycillin, erythromycin: Strep infections
Antivirals
Acyclovir: Cream, tablets and IV
Used for: Herpes simplex 1 and 2
Herpes zoster
(Cream useless on skin)
Side-effects: Practically none
Podophyllin: 25% in TBCo: Used for
condylomata acuminata and verrucae
Antiscabies
Benzoyl benzoate
Only effective treatment for scabies
Method of use: See lecture on skin
infections
Antihistamines
Sedating: Promethazine
Chlorpheniramine
Hydroxyzine (Aterax®)
Antihistamines
Sedating: Promethasine
Chlorpheniramine
Hydroxyzine (Aterax®)
Used for: Atopic dermatitis
Acute urticaria
Other forms of night-time pruritus
Antihistamines
Sedating: Promethasine
Chlorpheniramine
Hydroxyzine (Aterax®)
Used for: Atopic dermatitis
Acute urticaria
Other forms of night-time pruritus
Side-effects: Sedation (NB: Driving)
Photo-allergy (not hydroxyzine)
Dry mouth
Antihistamines
Non-sedating: Loratidine
Cetirizine
Desloratidine
Levocetirizine
Used for: Acute and chronic urticaria
Allergic rhinitis
Side-effects: Almost none
Anti-androgens
Cyproterone acetate
Progestogen, blocks 5α-reductase
2mg in Diane-35®
10mg in Androcur
Used mostly for acne
Side-effects: Depression, weight gain
Drosperinone
Ingredient of Yasmin®
Imiquimod (Aldara®)
Topical immunostimulant
Used for condylomata acuminata
Superficial spreading basal cell CA
Side-effects: Severe local inflammation