Paederus dermatitis, also known as dermatitis linearis is a peculiar irritant contact dermatitis characterized by erythematous and bullous lesions of sudden onset on exposed areas of the body. Iranian traditional medicine uses the S. ebulus in treating some inflammatory cases such as, bee and nettle bites, arthritis and sore-throat. In addition, it has been reported to be anti-bacterial, antioxidant, convenient in treatment of burns and infectious wounds, edema, eczema, urticaria, inflammation and rheumatism. These effects gave us a solid basis to make use of S. ebulus in treatment of paederus dermatitis. This study was designed to evaluate the clinical efficacy of S. ebulus 5% solution in patients affected by paederus dermatitis. Fruit were dried at room temperature and coarsely ground before extraction. Weighed amount of powdered sample was fractionated by successive solvent extraction at room temperature by percolation with hexane then ethyl acetate and finally methanol successively. To evaluate the clinical effect of ethanolic 5% solution, 60 patients will include blind and randomly in two groups, that administer S. ebulus ethanolic 5% solution or ethanol 70. All of patients will use a local hydrocortisone ointment too.The effects of drugs in terms of affecting on itching, burning, pain, inflammation, healing rate, drying the wound and infections will study. Four levels, namely, ineffective (value zero), average effect (value one), good effect (value two) and great effect (value three) chose for evaluation. All patients were visited or asked every 12 hr. The preparations will use locally 3 times a day. Only patient with the beginning of lesion less than 24 hours will enter to study. Any adverse drug reaction will considered, too.