roacetic acid 50% solution acts like phenol solution because
of its destructive effects. Trichloroacetic acid works through
the destruction of tissue by causing hydrolysis of cellular protein
and, finally, cell death. All currently available published
studies show that the effectiveness of TCA on genital warts is
comparable with cryotherapy, having response rates between
70% and 81%.10,11 A few studies have shown that TCA was effective
in treating cervical and anal warts.23-25 The effect of TCA
on virus-infected cells is nonspecific. A low concentration of
TCA (10%-30%) could be used for superficial peeling, and a
higher concentration (50%-90%) for moderate to deep peeling.
Trichloroacetic acid could also be helpful for skin diseases
such as xanthelasma palpebrarum and solar lentigines. Adequate
application is achieved when the wart and surrounding
area turn white. Trichloroacetic acid has the advantage of a
complete lack of systemic toxicity; it is not generally absorbed
systemically, and its treatment is delivered in a controlled
manner to provide limited local destruction, so it can be used
during pregnancy.3 Due to its rapid efficacy, TCA should be
used with special care around the eyes because white frosting
will appear after only a few minutes. The application of TCA is
accompanied by a burning sensation that lasts for two to five
minutes. Side effects are local pain, crust formation, infection,
ulceration, and rarely, scar formation.25
