Pharmacy 201

Spring 2002


Dermatologic Topics


The skin is the largest organ of the body it:


Each layer of skin has a specific task

  1. Top-epidermis-protects against harmful substances. Gives skin color from melanin.

  2. Dermis-contains pain & touch receptors, sweat glands, sebaceous glands (oil) and hair follicles

  3. Below Dermis-where fat is stored to help insulate from heat & cold


Most skin problems can be identified by looking at the size, shape, color and location. This tells the practitioner what it is.


Treatments

  1. Topical-apply directly to the skin

  2. Systemic-taken orally


Topical

Formulations include

  1. ointments-tick oil in water, hard to wash off, better delivery since medication stays on

  2. Creams-oil in water, easy to apply, vanishes into skin

  3. Lotions-just more water than in creams, easy to apply, easy to wash off

  4. Solutions-liquid in which drug is dissolved. Tend to dry rather than moisture

  5. Powders-dried form of a substance, finely pulverized, absorbs moisture

  6. Gels-water based, thickened without oil or fat, alcohol causes a drying effect


Sunburn

Sun induced skin damage ranges from sunburn to photoaging to pigmentary changes to solar keratosis to cancer.


Three types of radiation

UVC-germicidal radiation, not much reaches the earth, causes redness no tanning

UVB-sunburn radiation, skin cancer radiation, 10am-3pm peak exposure

UVA-after UVB most damaging range, goes deeper than UVB


The amount of UV rays reaching the skin depend on the season, location of the earth (equator), time of day (10am-3pm), clouds, snow, sand, fog, haze and humidity.


Tanning got its popularity in the 1950s. Tanned skin=good health. Prior to this tanned skin meant poor, laborer or farming.


Definition: Tan=uv radiation stimulates the melanocytes to generate more melanin this oxidizes in the epidermis to a tan


Sunburn-result of an inflammatory reaction. 1st degree is mild redness, tenderness, pain, edema

2nd degree is blisters, fever, chills, weakness





Beyond Sunburn is sun induced skin damage

  1. photoaging (Premature aging)-wrinkles & yellowing of skin, dryness, visible veins, up to 80% of the damage occurs by age 20

  2. Photodermatoses-skin eruptions caused by UVA & UVB **Lupus

  3. Drug Photosensitivity-Tetracyclines, sulfa drugs, hypoglycemics, thiazides, St. John's Wort, NSAIDS (ibuprofen), Cipro. Avoid the sun-use sunscreens

  4. Skin Cancer

  1. basal cell (face upper body, scalp, neck)

most at risk: blue or green eyes, light skin, blonde to red hair, English, Scandinavan, Scot-Irish ancestors. Childhood exposure with at least two major sunburns

  1. Squamous cell-risk always burn never tan, freckles

  2. Melanoma-less common but more deadly


ABCD

a-asymmetry of the lesion

b-irregular border

c-color variation, black, brown, bluish-red

d-diameter > 6mm


Be aware of any changes on head, neck, upper back


Sunscreens

SPF-Sun Protection Factor

The higher the SPF the more effective to a point

**If you burn in 30 minutes, then an SPF of 2 will give you an hour, SPF 4 gives you 2 hours

**however, applying SPF of 4 twice does not give you an SPF of 8


SPF of 15 blocks 93% of UVB

30 blocks only 96.7%

40 blocks only 97.5%


How to apply

  1. Apply at least 30 min prior to sun exposure

  2. Reapply often especially if swimming or sweating

  3. Big Mistake is missing spots

  4. Use ample amounts


Children < 6 months

American Academy of Pediatrics recommends using on hands, and exposed areas only. Cover the child. Just sitting under the umbrella is not enough


Seven Steps to Safer Sunning

  1. Avoid the sun between 10am & 3pm even on cloudy days

  2. Use sunscreen-broad spectrum covering UVA & UVB

  3. Wear a hat

  4. Wear sunglasses (wrap-arounds) check label for 99% blockage

  5. Cover up-avoid wet clothes-choose tightly woven

  6. Avoid tanning beds

  7. Check skin regularly








Fungal Infections

Over-the-counter products help prevent and treat symptoms. Can actually cure the problem


Tineas-skin, hair/scalp, nails


  1. Tinea pedis-athlete's foot

Occurs in up to 70% of adults

More commons in white patients

More common in males

Intense itching, scaly, peeling skin, red skin

May have an odor, may have tiny blisters

Skins cracks and peels


Try topical products first

Imidazoles

Clotrimazole 1% Lotrimin AF

Miconazole 2% Micatin

Tolnaftate 1% Tinactin, Aftate

Used regularly may prevent recurrences

Undecylenic acid Cruex

May have an unpleasant odor

Terbinafine Lamisil

Shorter treatment period, seven days, others are 14 days


Choose appropriate dosage form: ointment, cream, lotion, gels, powder, sprays, solutions


Prevent AF

  1. Keep feet clean & dry

  2. Dry between toes

  3. Go barefoot whenever possible

  4. Use shower shoes

  5. Change socks daily, rotate shoes, use cotton not synthetics

  6. Never share footwear

  7. If nail is involved, check with practitioner


  1. Tinea Corporis (Ringworm)

Ringworm-oval scaly patch, red border, treat topically first

For prevention and treatment


  1. Tinea Cruris-jock itch

Groin area, thighs, buttocks, intense itching, pain if sweat, secondary infection from scratching

Try OTC treatment first


  1. Tinea Capatis-ringworm of the scalp

Circular patch of scaling skin with hair loss. May have inflamed weeping lesion

Self OTC treatment is ineffective. These products can't penetrate the hair follicles. See practitioner for oral treatment. Don't share hats.


  1. Tinea Unguium (nail fungus)

Dull, opaque or yellow nails, nail thicken, brittle, crumble.

OTC ineffective, topicals don't penetrate the nail bed. Need RX oral and long term treatment.


  1. Tinea Versicolor

Irregular blotches, chest, abdomen, upper extremities

Does not respond well to OTC topicals




CONTACT DERMATITIS

Skin reaction that results form contact with some substance.


Those more prone to CD have fair skin, advanced age or certain occupations.


Poison Ivy-poison oak-sumac

Most common cause of CD at least 50 to 70% of the population is sensitive


Plants-small bush or tree like or vines "Leaves of Three, let it be"

If you are allergic to one then you will be to all three.


Person must come in contact with the plant, can't just "look at the plant"


Urushiol is the allergenic mixture. When plants are damaged, they are fragile, the sap leaks out. The sap contains the allergens.


Treatments:

  1. hydrocortisone-helps relieve the itching, use no more than 7 days

  2. diphenhydramine-DO NOT USE. May cause severe adverse effects if used on open blisters

  3. calamine, zinc oxide, kaolin, aluminum hydroxide-helps to dry the lesions

  4. coloidal oatmeal (Aveeno) and baking soda added to bath water helps relieve itching

  5. Wet dressings-Aluminum acetate-Domboro Solution

  6. Oral corticosteroids-RX only


Best advice



Field Test-break a stem or leaf. Touch the end with sap to white paper. Within 30 minutes the sap will oxidize to a brown-red to black color. "Black spot sign". Confirms identity of the plant


In most cases

  1. First exposure to plant. No reaction

  2. Second exposure, 5-21 days after get reaction

  3. Future exposure-48-72 hrs reaction


Cats & Dogs may transfer the allergen. Blisters don't transfer.