The most common finding of Loxosceles biting is a progresive ulcerous dermanecrosis. The responsible dermonecrotic factor found in the venom is Sphingomyelinase D. Poison effects are indicated by coagulation and occlusion which are the initial triggers of tissue necrosis in small capillaries. A 28 year old female patient was admitted after being bitten by a brown spider 3-4 hours earlier while putting on her shoes in the morning. There was a finding wit t a local inflammation on the medial proximal part of the right second toe. The following day, there was a medium grade edema reaching to the ankle, a large lesion colored in red-purple with undetermined borders and increased temperature on palpation. On the first day of hospitalization, RDW was 15.50, WBC was 11.20, neutrophil was 79.80%, lymphocyte was 11.30% on CBC, CRP was16, CPK was 455, LDH was 78 whereas the parameters of sedimentation, PT, PTT, blood gas were in normal ranges. An x-ray of the foot was taken. Stabilization and elevation of the extremity were provided. She was hospitalized due to Loxosceles poisoning in the Emergency Department for 5 days. The conservative treatment with fluid, antibiotics, corticosteroid, antiinflamatory drugs were initiated. The foot healed with a minimal pigmented dermal finding without any complication of tissue necrosis on the fourth week. The patient without any significant initial complaints and findings in insect bites should not confuse the clinician. The importance of observation of these patients is clear for control of probable complications and misdiagnosis cases. (JAEM 2013; 12: 101-4)