Phototoxicity pigmentation, skin

Serious side-effects have been associated with the important psychotherapeutic agent, chlorpromazine (358), almost since its introduction. High sensitivity to sunburn, pigmentation of the skin and ocular opacity are common phototoxic effects [ 196]. In a series of phenothiazines, the chloro-substituted compounds, particularly chlorpromazine, prochlorperazine and perphenazine, showed by far the greatest phototoxic activity [197, 198]. 

Toxicological Implications for Man. Because psoralens are potent photoactive compounds, they have been used medically for treatment of skin de pigment at ion or vitiligo (16,17), and psoriasis (18). However, there has recently been concern associated with the medical use of these compounds (19). This concern is due to the observed phototoxicity during therapeutic use (17), the suspected photocarcinogenicity of xanthotoxin (20,21), and the latent onset of tumors in treated laboratory animals (22). Acute gout secondary to psoriasis also was exacerbated by psoralen and UV-A (PUVA) photochemotherapy (23). 

Since C. cannot be distilled they also contain small amounts (1 -5%) of non-volatile components including pigments, waxes, coumarins, etc. The latter class of compounds also includes the so-called furocouma-rins, which are present in some C. at such concentrations that the application of these oils on the skin (e.g., as perfume) may lead to phototoxic reactions. These... 

Activity Many F. induce a brown pigmentation in the skin on exposure to sunlight. They are photosensitizing, phototoxic, and can induce allergic dermatitis (Berloque s dermatitis), possibly with severe symptoms such as blister formation. The effect can also arise when, for example, scented toilet waters whose plant components still contain F. are applied to the skin. Use In photochemotherapy for vitiligo, psoriasis, atopic dermatitis, mycosis togoides. Photoactivated F. bind covalently as haptens to proteins as well as pyrimidines of DNA and thus have antimitotic effects. For synthesis, see Lit.. ... 

This chapter will cover the state-of-the-art of in vitro human skin models and the utility of these models fdrug development applications including screening for skin sensitization, phototoxicity, irritation, genotoxicity, pigmentation effects, and percutaneous absorption. The validation status of the various models and applications and areas where further development is needed are also highlighted. 

Harber LC, Bickers DR (1989) Drug induced photosensitivity (phototoxic and photoallergic drug reactions). In Photosensitivity diseases principles of diagnosis and treatment, 2nd edn. Decker, Toronto, pp 160-202 Hare PJ (1951) A case of occupational iron pigmentation of the skin. Br J Dermatol 63 63-66... 

Triclocarban (TCC, trichlorocarbanilide, Cutisan, Nobacter, Solubacter, CAS no. 101-20-2). This is an antiseptic and bacteriostatic used in antimicrobial soap bars, deodorants, antiperspirants. Photoallergic and phototoxic reactions were reported (Hasan and Jansen 1996). Cross reaction occurs with other halogenated salicylanilides. Caustic reaction on skin and mucosa was reported (Barriere 1973). Allergic reactions are not uncommon, and can result in pigmentation afterwards. The patch-test concentration is 2% pet. 

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