Derm Pharm 1 Flashcards
choice of proper vehicle
- acute infl- drying preparations (tinctures, wet dressings, lotions)
- chronic infl- lubricating preparations (creams, ointments)
- drying preparations- scalp and hairy areas
- lubricating agents- intertriginous areas
topical antibacterial preparations
- Bacitracin, gramicidin
- mupirocin
- retapamulin
- polymyxin B sulfate
- neomycin, gentamicin
- topical abx in acne
Bacitracin, gramicidin- moa
- inhibits cell wall syn (bacitracin)
- inc permeability of cell wall (gramicidin)
- active against gram+ organisms
mupirocin- moa
- inhibits prot syntesis
- gram+ aerobic bacteria, including MRS
- tx impetigo caused by S aureus and group A B-hemolytic streptococci
retapamulin- moa
- binds to ribosomal 50S subunit and inhibits normal bacterial prot biosyn
- group A B-hemolytic streptococci and S aureus
Polymyxin B sulfate- moa
- inc perm of cell wall membrane
- gram-neg organisms (P aeruginosa, E coli, enterobacter, klebsiella)
- high levels- neurotoxicity, nephrotoxicity (rare)j
Neomycin and gentamicin- moa
- irreversibly binds 30S subunit and inhibits prot syn
- gram-neg organisms
- excreted in urine- renal failure may cause nephrotoxicity, neurotoxicity, ototoxicity
topical abx in acne
- clindamycin
- erythromycin
- metronidazole
- sodium sulfacetamide
Clindamycin- moa
- inhibits pro syn by reversibly binding to 50S ribosomal subunit
- serious infections due to S aureus
Erythromycin- moa
- inhibits prot syn- reversibly binds to 50S
- complications- abx resistance in staphylococci- discontinue topical tx and begin systemic abx tx
metronidazole- moa
- inhibit nucleic acid syn; anti-infl effects
- tx acne rosacea
- no in pregnancy or nursing
sodium sulfacetamide- moa
- inhibits P acnes- competitive inhibition of p-aminobenzoic acid utilization and inhibits bacterial folic acid syn
- contraindicated in pts w sensitivity to sulfonamides
Topical antifungal agents
- azoles
- ciclopirox olamine
- allylamines
- butenafine
- tolnaftate
- nystatin and amphotericin B
azoles- moa
- inhibit syn of ergosterol by inhibiting fungal cytochrome P450s
- tinea corporis, pedis, cruris, versicolor; cutaneous candidiasis
- clotrimazole and miconazole- prototype for Candidiasis
- often used with corticosteroid- more rapid sx improvement
Ciclopirox olamine- moa
- inhibits uptake of precursors of macromolecular syn
- topical dermatomycosis, candidiasis, tinea versicolor; onychomycosis
- poor efficacy
Allylamines- moa
Terbinafine, naftifine
- inhibits squalene epoxidase (key enzyme in ergosterol biosyn)
- tinea corporis, cruris, pedis
Butenafine- moa
-similar to allylamines
Tolnaftate- moa
- cutaneous mycoses; but ineffective against candida
- tinea pedis, cruris, corporis
- unknown moa
Nystatin and amphotericin B- moa
- binds to ergosterol in fungal cell memb and alters memb permeability- loss of K and other cell constituents
- Nystatin topical uses- used for oral candidiasis
- Amphotericin B- used IV; infusion related toxicity and cumulative organ toxicity (kidney in almost all pts)- “Ampho-terrible”
Oral antifungal agents
- azoles
- griseofulvin
- terbinafine
Oral antifungal agents- azoles
- vaginal, urinary, oropharyngeal candida infections
- itraconazole and fluconazole- prototype
- many drug-drug interactions
Oral antifungal agents- griseofulvin- moa
- inhibits fungal cell mitosis and binds to human keratin, making it resistant to fungal invasion
- tx dermatophyte infections; but not candida
- induces hepatic CYPs
Antiviral agents- topical
- Acyclovir, valacyclovir, penciclovir, famciclovir
- docosanol
Acyclovir, valacyclovir, penciclovir, famciclovir- moa
- converted to active triphosphate metabolites and inhibit viral DNA syn and viral replication
- oral- herpes labialis
- topical- recurrent orolabial HSV infection in immunocompromised pts
Docosanol- moa
- inhibits fusion b/w plasma memb and HSV envelope, preventing viral entry and replication
- orolabial herpes
Antiviral agents- sytemic
-acyclovir, famciclovir, valacyclovir- can be used for HSV and VZV infections
Immunomodulators
- imiquimod
- tacrolimus
- pimecrolimus
Imiquimod- moa
- external genital and perianal warts, actinic keratoses on face and scalp, primary BCCs on trunk, neck, and extremities
- moa- unknown
tacrolimus and pimecrolimus- moa
- tx atopic dermatitis (second-line)
- inhibits T-lymphocyte act and prevents release of infl cytokines from mast cells
- long-term safety is not esta- dont use in immunocompromised or < 2 yo
Acne preparations
- retinoids
- benzoyl peroxide
- azelaic acid
- brimonidine
Retinoids- topical
- Tretinoin
- Adapalene
- Tazarotene
Tretinoin
- moa unknown
- SEs- erythema, mild peeling, dryness; avoid sun exposure (inc photosensitivity rxns)
- initially may aggravate acne
Adapalene
- less irritating than tretinoin
- mild/moderate acne vulgaris
Tazarotene
- psoriasis, photoaging, acne
- teratogenic
Retinoids- oral
Isotretinoin (Accutane)
- reduces sebaceous gland size and reduces sebum production
- tx unmanageable severe cystic acne, psoriasis, cutaneous malignant neoplasms
- teratogen
Benzoyl peroxide- moa
- releases free-radical oxygen which oxidizes bacterial proteins in the sebaceous follicles- dec the # of anaerobic bacteria and dec irritating-type free fa’s
- antimicrobial activity against P acnes
Azelaic acid- moa
-antimicrobial against P acnes and in vitro inhibitory effects on the conversion to T to DHT
Brimonidine- moa
- alpha-2 adrenergic agonist- dec erythema via direct vasoconstriction
- only for > 18 yo
