Topical Medications Flashcards
Dependent Factors of Success of Dermatologic Therapies
Correct diagnosis Type of lesion treated Medication used Vehicle (cream, ointment, etc.) Method used to apply medication
What does the vehicle determine?
Rate at which the active ingredient is absorbed through the skin
Components of the Vehicle
Solvents Stabilizers Emollients Humectants Thickening agents Emulsifying agents
What is acute inflammation treated with?
Aqueous drying preparations
What is chronic inflammation treated with?
Greasy, lubricating compounds
Important Factors of Drug Penetration
Method of topical application
Site of application
Thickness of epidermal layer
Define Tachyphylaxis
Progressive decrease in clinical response due to repetitive application of drug
Similar to tolerance
Solution for Tachyphylaxi
Drug free intervals
Switch at various times to alternative agents (down a strain, different base)
3 Basic Ingredients of Vehicles
Powder
Oils
Liquids
Types of Vehicles
Powders Solutions Tinctures Lotions Oils Ointments Creams Gels Aerosols & Sprays Shampoos Foam
What vehicles should we be most concerned about?
Ointments
Lotions
Creams
Gels
What do powders aid in?
Absorbing moisture
Decrease friction
Help cover wide areas easily
Where is the best place to use powders?
Intertriginous areas
Define Solutions
Lotions with very minimal oil or solid content, but with active ingredients
Ex: Visine
Define Tinctures
Alcoholic or hydroalcohoic solutions
Define Lotions
Suspension of powder in water
Define Shake Lotions
Solids are suspended within
Ex: Calamine lotion
Define Emollient Lotions
Oils dispersed in the water usually with surfactant
Where are lotions useful?
Hairy areas
Conditions where large areas have to be treated
Least Potent Topical Therapy
Lotions
Define Creams
Semisolid emulsions of oil in water about equal proportion
Penetrates stratum corneum well
Define Ointment
Water droplets suspended in the continuous phase of oil or of inert bases
Ex oil: mineral oil
Ex inert bases: petrolatum (vaseline)
Use of Ointments
Most lubricating & moisturizing
Facilitates heat retention
Semi-occlusive
Non-seborrheic, non-intertriginous areas
Most Potent Vehicle
Ointment
Define Gels
Transparent semisolid emulsion that liquefies on contact with skin
Dries as thin, greaseless, non-occlusive film
Uses for Gels
Seborrheic areas (face, chest)
Considered drying
Exudative inflammation (poison ivy)
Acne (Retin-A)
Aerosols & Sprays
Alcohol based solutions Pressurized Considered drying Wasteful Scalp most frequently
Define Foams
Pressurized collections of gaseous bubbles in a matrix of liquid film
Shampoo uses
Seborrheic dermatitis of the scalp
Main Educational Point of Shampoos
Left on for 5-7 minutes
What is the strength of a topical medication dependent on?
Vehicle
Most Potent, Potent, & Least Potent Vehicle
Most: ointment/gel
Middle: cream
Least: lotion
MOA of Topical Glucocorticoids
Pass through stratum corneum
Cause vasoconstriction
Decrease inflammation
Inhibit cellular proliferation
How are steroids ranked in potency?
Extensiveness of vasoconstriction
Indications for Topical Glucocorticoids
Therapy of choice for most inflammatory conditions
Pruritic eruptions
Hyperplastic disorders
Infiltrative disorders
Desirable Qualities of Corticosteroids
Broad applicability Rapid action with small dose Ease of use Lack of sensitization Prolonged stability Combatible with most topical medications
Adverse Reactions with Topical Corticosteroids
Suppression of hypothalamic-pituitary system
Local reactions
Local Adverse Reactions to Topical Corticosteroids
Burning, itching, dryness (vehicle related) Atrophy & telangiectasias Irreversible stretch marks Skin fragility & easy bruising Steroid rosacea
Location of Greatest Penetration of Topical Corticosteroids
Genetalia
Location of Least Penetration of Topical Corticosteroids
Sole of foot
Factors that Affect Topical Corticosteroid Penetration
Thickness of area Skin hydration (increased = increased absorption) Inflamed skin (increased penetration)
4 Groups of Topical Steroids
Super potent
Potent
Intermediate
Mild
Super Potent Topical Steroid Uses
Severe non-facial/non-intertriginous dermatoses Palms & soles Psoriasis Severe atopic dermatitis Severe contact dermatitis
Intermediated to Potent Topical Steroid Uses
Mild-moderate non-facial/non-intertriginous dermatoses
Mild-Intermediate Topical Steroid Uses
Large areas are treated (due to systemic absorption)
Mild Topical Steroid Uses
Eyelid dermatoses
Genital dermatoses
Frequency of SE of Mild Topical Steroid Use
Rarely
Intermittent therapy for long term use
Frequency of SE of Potent & Intermediate Topical Steroid Use
Rarely if
Length of Time for Super Potent Topical Steroid Use
What areas are most susceptible to atrophy, telangiectasia, & acneiform eruption?
Facial
Intertriginous
Genital
What increases systemic absorption in topical steroid use?
Application to highly permeable areas
Topical Steroid Use in Children
Low potency
What can help diagnose a fungus from an inflammatory dermatitis?
KOH scraping
Examples of Topical Antibacterials
Mupirocin (Bactroban)
Neomycin
Gentamycin
Silver Sulfazine
Benefits of Topical Antibacterials
Treat a wide variety of potential pathogens
No risk of ototoxicity or nephrotoxicity from aminoglycoside topicals
Drug concentration can be very high
Drugs are in more direct contact with organisms
Combinations of various antibacterials are synergistic
Topical use helps to retard the emergence of resistant organisms
Bactroban (Mupirocin)
Ointment & cream
Bugs: staph, strep, E. coli, H. flu, N. gonorrhea
TREAT IMPETIGO
Neomycin
Ointment & cream
Bugs: gram negatives (except Pseudomonas)
50 times more active against Staph
Greater risk of allergic contact sensitivity
Gentamycin
Ointment or cream
Bugs: staph, group A beta-hemolytic strep, PSEUDOMONAS
Silvadene: Silver Sulfadiazine
1% cream
Bugs: gram-positives, gram-negatives, candida albicans
NOT WITH SULFA ALLERGY
Leukopenia in burn patients
When to use silvadene: silver sulfadiazine?
2nd/3rd degree burns
Chronic ulcers
Stasis ulcers
Examples of Topical Anti-fungal Agents
Polyene class Allayment class Others
MOA of Polyene Class of Anti-fungal Agents
Bind with sterols in fungal cell membrane
Changes temp of cell membrane from fluid to crystalline state
Leakage of ions & small organic molecules
Cell death
Drugs in the Polyene Class of Anti-fungal Agents
Nystatin (Mycostatin) Amphotericin B (Fungizone)
Nystatin
Ointment, cream
Treat Candida infections
Oral preps poorly absorbed, no systemic or cutaneous infections
Amphotericin B (Fungizone)
RX only 3% cream, lotion, or ointment Topically treat Candida albicans Ineffective against dermatophytes (ring worm) & tinea versicolor May stain clothes
MOA of Allyamine Class
Inhibit squaline epoxidase
Enzyme necessary for ergosterol synthesis
Allyamine Class Medications
Terbinafine (Lamisil)
Naftitine (Naftin)
Terbinafine (Lamisil)
OTC
1% cream
Dermatophytes (ring worm)
Naftifine (Naftin)
RX only
1% or 2% cream, gel, or powder
Topical of tinea corporis, cruris, and versicolor
MOA of Imidazole Class
Inhibits lamosterol 14 alpha-demathylase
Leads to inhibition of fungal growth
Imadazole Class Medications
Clotrimazole (Lotrimin, Desenex)
Miconazole (Micatin, Monostat)
Ketoconazole (Nizoral)
Clotrimazole (Lotrimin, Mycelex)
OTC
Cream, solution
Treat tinea corporis, tinea pedis, tinea cruris, tinea versicolor
Miconazole (Monistat, Micatin)
OTC
2% cream, lotion, vaginal suppositories
Treat vaginal infections due to candida albicans, tinea pedis, tinea cruris, tinea corporis, & tinea versicolor
Examples of Imidazole Anti-fungals
Ketoconazole (Nizoral)
Econazole (Spectazole)
Ketoconazole (Nizoral)
RX
2% cream: tinea infections & tinea versicolor
2% shampoo: seborrheic dermatitis
Econazole (Spectazole)
RX
1% cream
Treat tinea corporis, tinea pedis, tinea cruris, tinea versicolor
Other Anti-fungals
Ciclopirox Oxamine (Loprox) Selenium sulfide (Selsun, Exsel) Tolnaftate (Tinactin, Cruex)
Ciclopirox Oxamine (Loprox)
RX
Broad spectrum anti-fungal agent
Interferes with cell membrane transport & fungal respiratory process
1% cream & lotion: dermatophytes, C. albicans & tinea versicolor
8% Penlac nail lacquer: mild to moderate onychomycosis
Selenium Sulfide (Selsun, Exsel)
OTC
MOA: anti-mitotic, anti-bacterial, anti-fungal
1% & 2.5%
Treat: seborrheic dermatitis, dandruff, & tinea versicolor
Tolnaftate (Tinactin, Cruex)
OTC
Believed to inhibit squalene epoxies
10% cream, powder, spray, ointment
Treat: tinea versicolor, dermatophyte fungi
Examples of Acne Preparations
Azalea acid Benzoyl peroxidase Retinoids Topical antibiotics Dapsone
Azelaic Acid
MOA: reduces the populations of P. acnes
Treat: mild to moderate inflammatory & non-inflammatory acne
SE of Azelaic Acid
Skin dryness
Lightening of the skin
Benzoyl Peroxide
OTC
MOA: killing P. acne
No anti-inflammatory abilities
Vehicle: gel, lotion, cleanser, cream, & wash
Increases effectiveness of erythromycin & clindamycin
SE of Benzoyl Peroxide
Skin irritation
Bleach hair & fabrics
Allergic reaction
Topical Retinoids
Treats mild to moderate severe acne
Anti-inflammatory
Unclog pores
Diminish signs of aging
SE of Topical Retinoids
Irritate the skin
Increase sun sensitivity
Retinoid Acid (Retin-A)
Acid form of Vitamin A
Decreases cohesion between epidermal cells
Increased epidermal cell turnover
Expulsion of open comedones
Transform closed comedones to open ones
Promotes collagen synthesis, new blood vessel formation & thickening of the epidermis
Adapalene (Differin)
Mild retinoid
0.1% gel
Less irritating than Retin-A
Mild to moderate acne vulgaris
Tazarotene (Tazorac)
0.1% gel & cream
Mild to moderately severe facial acne & psoriasis
>12 year old
Pregnancy category X
SE of Acne Preparations
Erythema
Dryness
Sun sensitivity
Education with Retinoids
Don’t put retinoid with benzoyl peroxidase
BP oxidizes the retinoid
Topical Antibacterials for Acne
Clindamycin
Erythromycin
Sodium sulfacetamide
Clindamycin
1% solution or gel
Come in fixed dose with benzoyl peroxidase
Formulations: water based gel & lotion
Erythromycin
1st line
Use with benzyl peroxide
Not as monotherapy
Sodium Sulfacetamide
Treats acne vulgaris & acne rosacea
NOT FOR SULFA ALLERGIES
Dapsone 5%
Anti-inflammatory
Anti-bacterial
Dapsone + benzyl peroxide = orange skin
Topical Medications for Parasitic Infections
Permethrin cream
Lindane lotion
Ivermectin
Permethrin Cream
OTC RX for lice & scabies Med of choice for children Pruritus may continue Apply to entire body Kills mite Family should be treated Clothing & bedding washed
Permethrin Cream Rinse
Treat lice
Reapplied after 14 days
Fine tooth comb to remove nits
Lindane Lotion
Older children & adults
Second treatment required 2 weeks later
Ivermectin (Stomectol)
2 doses given a week apart
Helpful for severe infestations in immunocompromised system
Topical Immunosuppressive Medications
Tacrolimus (Protopic)
Pimecrolimus (Elidel)
2nd Line Treatment for Mild to Moderate Atopic Dermatitis
Topical Calcineurin Inhibitors
MOA of Topical Calcineurin Inhibitors
Inhibits effects of cytokine production but also may result in a decreased activity of T cells
Topical Calcineurin Inhibitors SE
Mild stinging
Burning
Pruritis
Medication class that increases the risk of developing lymphomas & skin cancer
Topical Calcineurin Inhibitors
Contraindications for Topical Calcineurin Inhibitors
Topical Meds for Skin CA & Actinic Keratosis
5-FU
Imiquimod
MOA of 5-FU (Efudex)
Interferes with DNA synthesis
Primarily in the fastest growing cells
5-FU Treats what Diseases
Actinic keratosis
Low grade BCC
Results of 5-FU on the Skin
Burning, peeling, blistering skin
Sun sensitive
MOA of Imoquimod
Immune modifies
Promotes apoptosis in skin cancer cells
Imoquimod Treats what Diseases
BCC
Actinic keratosis
Genital warts
Effects of Imoquimod on the Skin
Burning, peeling, blistering skin
Sun sensitive
Systemic fatigue
Flu-like illness
