Topical Agents

Monotherapy with topical retinoids has been shown to facilitate resolution of PIH. A random- 

The concomitant use of various bleaching agents has also been shown to improve PIH. In 1975, tretinoin in combination with hydroqui-none and dexamethasone was reported as an effective treatment for PIH [14]. In a small study, the application of 2% hydroquinone and 10% glycolic acid gel twice daily and 0.05% tretinoin cream at night has been shown to provide benefit for darker-skinned patients with PIH [15]. Similarly, Yoshimura et al. [16] suggested efficacy of tretinoin combined with hydroquinone and lactic acid in reducing PIH. More re- 

Superficial chemical peels, including salicylic and glycolic acids, and Jessner s peels target the stratum corneum to the papillary dermis. These agents can be safely used to facilitate the resolution of PIH (Figs. 16.2,16.3,16.4 and 16.5). To assess for variability in response and limit further PIH, when possible, chemical peels should be initiated at the lower concentrations and titrated to higher concentrations if necessary to increase efficacy while minimizing side effects (see Darker Skin Section). 

Superficial salicylic acids have been shown to be safe and efficacious for treatment of PIH. In a study of five patients with Fitzpatrick s Skin Types V and VI with PIH, pretreatment for 2 weeks with hydroquinone 4% cream followed by a series of five 20-30% salicylic acid chemi- 

Haider RM, Grimes PE, McLaurin Cl, Kreiss MA, Kenney JA (1983) Incidence of common dermatoses in a predominantly black dermatologic practice. Cutis 32(4) 388,390 

Antifungal drugs are frequently administered by topical application to control superficial infections of the skin. It is important to remember that products formu- 

Sensitisation to modern antifungal drugs is not a common experience. It has been reported, and confirmed by adequately controlled patch tests, to tolnaftate (Gellin et al. 1972 Emmett and Marks 1973), to the polyene antibiotic, pecilocin (SuNDERARAJAN 1970 Groen et al. 1973 Norgaard 1977), chlordantoin (Epstein 1966), haloprogin (Rudolph 1975 Sturde 1975 Hollander 1977) and to fluonilid (Van Hecke 1969), but cases are sufficiently unusual for even individual case reports to be noted (Fig. 4). 

In view of the relative ease with which low molecular weight chemical substances can sensitise human skin if applied frequently over a period of time, this low level of sensitisation must reflect the value of predictive testing of topical agents in volunteers and in patients by methods now well established (Draize 1959 Kligman 1966 a, b). 

The older antifungal agent, phenylmercuric borate, used still in the control of athlete s foot, is a more common and more potent skin sensitiser. In a trial reported by Bandmann (1966) more than 10% of patients developed contact allergic dermatitis, and cross-reactions with other mercury compounds can occur. 

Sensitisation to the topical antifungal agent, Mycanodin is difficult to quantitate. The active antifungal is 3-(2-hydroxy-5-chlorophenyl)pyrazole and this can cause contact allergic dermatitis and photoallergic reactions (Fig. 4 Burckhardt et al. 1968). The same authors showed, however, that an antihistamine co-formu- 

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P.G. Unna, a German dermatologist, was the first to describe the properties and use of salicylic acid. It has since been used for many decades as a keratolytic agent in concentrations of 3 to 6%. Salicylic acid is frequently utilized in topical acne preparations because of its comed-olytic effects. In addition, it facilitates the penetration of other topical agents. 

Dorfman D, Dalton A et al (1999) Treatment of painful distal sensory polyneuropathy in HIV-infected patients with a topical agent results of an open-label trial of 5% lidocaine gel. AIDS 13(12) 1589-1590... 

There are two main approaches to pharmacologic intervention for pain relief oral (systemic) and topical agents. 

Treatment of musculoskeletal disorders involves three phases (1) therapy of an acute injury using the RICE principle, (2) pain relief using oral or topical agents, and (3) lifestyle and behavioral modifications for rehabilitation and to prevent recurrent injury or chronic pain (Fig. 57-3). 

Treatment of ocular allergy is aimed at slowing or stopping these processes. Antihistamines block the histamine receptors and some prevent histamine production and/or inhibit mediator release from the mast cells.15 Mast cell stabilizers inhibit the degranulation of mast cells, preventing mediator release. Some topical agents have multiple mechanisms of action, combining antihistaminic, mast cell stabilization, and antiinflammatory properties (Tables 60-3 and 60-4).16... 

If mast cell stabilizers or multiple-action agents are not successful, a trial of a topical NSAID is appropriate. Ketorolac is the only approved topical agent for ocular itching. NSAIDs do not mask ocular infections, affect wound healing, increase intraocular pressure, or contribute to cataract formation like the topical corticosteroids. However, for allergic conjunctivitis, topical ketorolac is not as effective as olopatadine or emedas-tine in trials.15 Full efficacy of ketorolac takes up to 2 weeks.17... 

Pharmacologic alternatives for psoriasis include topical agents, phototherapy, and systemic agents including the use of biologic response modifiers. 

Topical agents may be incorporated into various vehicles including ointments, creams, gels, lotions, foams, pastes, and shampoos. Ointments provide occlusion which may increase... 

Pharmacologic Therapy Topical Agents Benzoyl Peroxide... 

Sulfur, resorcinol, and salicylic acid are not as effective as other topical agents, but can be used as second-line therapies in the treatment of mild to moderate acne.12... 

Cidofovir 0.3%, 1%, and 3% topical agent used on a compassionate basis for acyclovir-resistant herpes lesions (3-7 days) Application site reactions, lesion recrudescence... 

Trifluridine 1% topical agent used for acyclovir-resistant herpes infections for 7-14 days Transient burning or stinging, palpebral edema, superficial punctuate, keratopathy, changes in intraocular pressure... 

Topical agents are first-line therapy for oropharyngeal candidiasis, although oral agents maybe used for severe or unresponsive cases. 

Onychomycosis, fungal infections involving the nails, requires oral antifungal therapy. Topical agents do not adequately penetrate the nail. 

Onychomycosis is a chronic infection that rarely remits spontaneously. Adequate treatment is essential to prevent spread to other sites, secondary bacterial infections, cellulitis, or gangrene. Due to the chronic nature and impenetrability of nails, topical agents have low efficacy rates for treating onychomycosis. Oral agents that can penetrate the nail matrix and nail base, such as itraconazole and terbinafine, are more effective than ciclopirox lacquer. Itraconazole and terbinafine demonstrate mycological cure rates of 62%37 and 76%,38 respectively, while ciclopirox has a cure rate of 29% to 36%.39... 

Imiquimod is an immune response modifier that has the ability to activate acquired and innate immune response. It is a topical agent that has been shown to be effective for SCC in case reports. It has been studied more extensively in superficial and nodular BCC, with response rates of 70% to 88%.72 The most common side effects are erythema, itching, pain, and crusting... 

Of a series of indanylthiocarbamates, to1 indate (2) had significant antifungal properties. It is prepared simply from 5-indanyl thionochloroformate (1) by reaction with N-methyl-m-toluidine. It presumably joins the fairly large family of organic compounds having sulfur divalently bound to carbon which are useful topical agents for dermatophytes. 

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