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(6) Ultraviolet radiation (UV) has long been recognized as a safe and eff ective treatment for managing psoriasis. Varying types of phototherapy are available to patients. All phototherapy treatment regimens should be initiated and managed by a physician or dermatologist.

III. FUNGAL INFECTIONSA. Overview

1. Fungal skin infections, also known as tineas or ringworm (due to its characteristic circular appearance), are some of the most commonly encountered dermatologic conditions. It is esti-mated that up to 20% of the American population may be infected with a tinea infection at any given time.

2. Several factors may predispose people to becoming infected with a tinea. Fungi grow best in warm, moist environments. Tight clothing or shoes that are worn on a repeated basis may fa-cilitate fungal growth. Sharing public showers or pools can also promote the spread of tinea in-fections. Patients with diseases or conditions that suppress the bodys natural immune response (such as diabetes, poor personal hygiene, malnutrition, or a compromised epithelium) are at greater risk of contracting tinea infections.

3. Nonprescription therapies usually work quite well in resolving many types of tinea infections completely.

B. Pathophysiology1. Tinea infections are typically superfi cial. Th e fungi that cause tineas thrive on dead skin cells

within the stratum corneum. Skin, hair, and nails may all be aff ected by a tinea infection.2. Th e three most prevalent fungi in the United States that cause tinea infections are Trichophyton,

Microsporum, and Epidermophyton.3. Fungi may be transmitted to an unaff ected individual either through direct contact with an in-

fected person or animal or through contact with a fomite.C. Clinical presentation. Tineas are categorized by the area of the body they aff ect.

1. Tinea capitis is also known as ringworm of the scalp. Tinea capitis occurs more frequently in chil-dren than adults. Th is may be due in part to a lack of social inhibition in sharing items like brushes and combs. Epidermal gland secretions also increase at puberty and have a fungicidal eff ect.

2. Tinea corporis, or ringworm of the body, is not limited to a specifi c area of the body. Rather, tinea corporis may take on several clinical appearances and can aff ect any area of the body. Oft en, patients with tinea corporis are infected with one or more additional tineas.

3. Tinea cruris is more commonly referred to as jock itch. Th e intertriginous areas of the groin make it an ideal environment for fungal infections. For anatomical reasons, males are more likely to suff er from tinea cruris than females.

4. Tinea nigra is perhaps the least common of the tineas. It is mainly seen in people who live in hu-mid coastal areas and may be transmitted through sand. Tinea nigra is primarily found on fi ngers and feet.

5. Tinea pedis, or athletes foot, is by far the most common tinea infection. Sports players and people who share pools or showers are at the greatest risk for contracting tinea pedis. Once present, athletes foot is exacerbated in patients who continue to wear shoes and socks, fostering a warm and moist environment for the fungus to survive.

6. Tinea unguium, or onychomycosis, is a fungal infection of the nails. Toenails are more fre-quently aff ected by tinea unguium than fi ngernails. Onychomycosis can ultimately lead to loss of the aff ected nail if not treated appropriately.

7. Tinea versicolor is a chronic fungal infection of the skin. Tinea versicolor is caused by Pityrospo-rum (see II.B.2) and primarily aff ects people living in hot, humid climates.

D. Treatment1. Nonpharmacological measures

a. To maintain proper hygiene and to minimize the likelihood of contracting a tinea or spread-ing a tinea to another person, patients should wash their body daily with soap and water.

b. Any contaminated towels and clothing must be washed in hot water.c. Patients with tinea infections should be counseled to avoid sharing towels.d. Allow shoes and clothing to dry completely before wearing them.

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Over-the-Counter Dermatological Agents 401

e. As much as possible, noninfected patients should avoid direct contact with and avoid using the same showers as people who have fungal infections.

f. If a shower must be shared, patients should be counseled to wear shower shoes/sandals while in the shower.

2. Pharmacological therapiesa. Nonprescription topical medications

(1) Only three types of tinea infections respond to self-treatment with nonprescription thera-pies: tinea corporis, tinea cruris, and tinea pedis. All other tinea infections should be referred to a physician for evaluation and treatment.

(2) Each of the antifungals listed in the following text is applied topically for 1 to 4 weeks. Th ese agents are generally well-tolerated, and systemic side eff ects are rare.(a) Butenafi ne (Lotrimin Ultra) is available as a 1% cream. Butenafi ne should only be

used in patients 12 and older.(b) Clotrimazole (Desenex AF Cream, Lotrimin AF Lotion) is also sold as a 1% cream,

lotion, or solution. Some patients will experience mild burning and stinging with use of clotrimazole.

(c) Miconazole (Cruex Antifungal Spray Powder, Micatin Jock Itch Cream) is a 2% powder, cream, or lotion and is closely related chemically to clotrimazole.

(d) Terbinafi ne (Lamisil AT) is available as a 1% cream, gel, or spray. Like butenafi ne, terbinafi ne should only be recommended in patients age 12 and older.

(e) Tolnaft ate (Tinactin) is a 1% cream, gel, or powder that has served as the OTC stan-dard of care for fungal infections for decades (prior to many of these other products being introduced). Tolnaft ate is the only active ingredient that carries FDA approval for both the treatment and prevention of athletes foot, when used on a daily basis.

(f) Undecylenic acid (Cruex Cream, Fungicure Liquid) is marketed in concentrations of 10% to 25% and comes in multiple forms, including a cream, solution, powder, and spray. Products containing undecylenic acid and its salts carry an unpleasant odor, which may be unacceptable to some patients.

b. Prescription treatment options. Patients who do not respond to self-treatment with any of the OTC therapies described previously within 1 week should be referred to their primary care provider for evaluation. If the condition shows improvement within the fi rst week, pa-tients are free to continue with self-treatment.(1) Topical antifungals are available for use in patients who do not experience resolution

of their tinea infection with OTC therapies or who have a tinea infection that cannot be self-treated.(a) Ciclopirox (Loprox) is available as a cream, gel, or lacquer for the treatment of tinea

corporis, cruris, pedis, versicolor, and unguium.(b) Econazole (Spectazole) 1% cream is indicated for the treatment of tinea corporis,

cruris, pedis, and versicolor.(2) More severe fungal infections require treatment with systemic therapies.

(a) Th e azole antifungals [fl uconazole (Difl ucan), itraconazole (Sporanox), ketocon-azole (Nizoral), posaconazole (Noxafi l), and voriconazole (Vfend)] are generally well-tolerated. Th e azoles may cause varying degrees of hepatotoxicity, and the class is notorious for its wide spectrum of drugdrug interactions.

(b) Griseofulvin (Grifulvin V) is available as both an oral tablet and suspension. Because griseofulvin increases photosensitivity, patients taking this agent should avoid pro-longed exposure to the sun.

(c) In addition to its status as an OTC topical agent, terbinafi ne (Lamisil) is also available as a prescription oral antifungal. It is considered the fi rst-line agent for onychomycosis.

IV. ACNEA. Overview

1. Defi nition. Acne vulgaris is a disorder of the pilosebaceous units, mainly of the face, chest, and back. Th e lesions usually start as open or closed comedones and evolve into infl ammatory papules and pus-tules that either resolve as macules or become secondary pyoderma, which results in various sequelae.

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