{'fraction_non_alphanumeric': 0.017934782608695653, 'fraction_numerical': 0.004891304347826087, 'mean_word_length': 5.016339869281046, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Treatment of lichen planus. An evidence-based medicine analysis of efficacy.

OBJECTIVE
To critically appraise the body of literature concerning treatment of lichen planus (LP).


DESIGN
Review of MEDLINE and BIOSIS databases to identify articles published with at least an English abstract before March 1998 that examined treatment of LP.


MAIN OUTCOME MEASURES
Forming a primary database on which most recommendations are based. We thus selected 83 clinical trials or small series of patients in the medical literature that referenced clinical data on patients treated for LP.


RESULTS
There are no large randomized trials with definitive results in the medical literature examining the efficacy of the various drugs or physical treatments of LP. There are only 3 level B trials (small randomized trials with uncertain results because of moderate to high alpha or beta error) that address efficacy of treatment in LP, i.e., 1 with acitretin in cutaneous LP and 2 with topical corticosteroids in mucosal LP. The remainder of the published trials are observational and are not always prospective. Many of the recommendations of the experts are based on their personal experience.


CONCLUSIONS
Although LP may be associated with substantial morbidity and altered quality of life, especially the erosive mucosal LP, definitive clinical trials have not been performed. Acitretin is the first-line therapy in cutaneous LP. The efficacy of systemic corticosteroids and psoralen plus UV-A therapy has not been established with a high level of proof. Topical corticosteroids are the first-line therapy in mucosal erosive LP. Other treatments, such as topical cyclosporine or extracorporeal photochemotherapy, remain to be evaluated. European-US cooperation is warranted to perform large randomized controlled trials in cutaneous and mucosal LP.