The purpose of this study is to investigate whether topical applied pimecrolimus will lead to improvement of erosive oral lichen planus. This effect will be monitored by reduction of erosive mucosal area and reduction of patient's pain symptoms.

Oral lichen planus is a mucosal inflammatory disease of unknown origin. It can be very painful especially if erosions appear on the oral mucosa.

In this study the efficacy of pimecrolimus compared to placebo in treatment of erosive oral lichen planus will be investigated. To this end the subjective pain and the amount of affected mucosa will be monitored before and after treatment.

Inclusion Criteria:

• Clinically and histologically confirmed diagnosis of erosive oral lichen planus
• Spontaneous or meal related oral pain
• No topical therapy 2 weeks prior to study start
• No systemic therapy 4 weeks prior to study start
• Signed informed consent

Exclusion Criteria:

• Pregnant or breast-feeding women
• Known allergy to macrolide antibiotics
• Known current active malignant disease or in patient's history
• Known immunodeficiency or HIV infection
• Participation at another clinical trial within the last 6 months