Pityriasis rosea (pityriasis - fine scale, rosea-red) Acute self limiting papulo- squamous disorder mainly occurring in children and young adults. Etiology: Infection - HHV6/7 Drugs causing PR- arsenic, bismuth, gold, omeprazole, metronidazole,isotretinoin,barbiturates, clonidine, captopril, imatinib , ketotifen Others- Hepatitis B, BCG vaccination. Characteristic features of PR indicating infective etiology 1: history of preceeding ui 2: primary lesion followed after an interval with widespread rash 3: self limiting course 4: recurrence is rare Clinical features: 1. Age - 10-35 years 2. First manifestation -HERALD patch or mother patch- seen in 50% of patients. Erythematous well defined oval lesion 2-10 cm diameter with typical colarette of scale at margin 3. After 5-15 days wide spread rash in crops. Oval round erythematous scaly plaques 0.5-1.5cm with colate of fine scales at margin. Free edge of scale points to center. 4. Distribution - CHRISTMAS tree or FIR tree pattern- long axis of lesions along skin tension lines running parallel to ribs 5. Spontaneous resolution in 3-6weeks Treatment: Reassurance, self liming disease Symptomatic rx- calamine emollients, antihistamines, topical steroids Erythromycin , acyclovir,NBUVB can be given at acute stages IADVL textbook of dermatology,page 375 Pityriasis rosea (pityriasis - fine scale, rosea-red) Acute self limiting papulo- squamous disorder mainly occurring in children and young adults. Etiology: Infection - HHV6/7 Drugs causing PR- arsenic, bismuth, gold, omeprazole, metronidazole,isotretinoin,barbiturates, clonidine, captopril, imatinib , ketotifen Others- Hepatitis B, BCG vaccination. Characteristic features of PR indicating infective etiology 1: history of preceeding ui 2: primary lesion followed after an interval with widespread rash 3: self limiting course 4: recurrence is rare Clinical features: 1. Age - 10-35 years 2. First manifestation -HERALD patch or mother patch- seen in 50% of patients. Erythematous well defined oval lesion 2-10 cm diameter with typical colarette of scale at margin 3. After 5-15 days wide spread rash in crops. Oval round erythematous scaly plaques 0.5-1.5cm with colate of fine scales at margin. Free edge of scale points to center. 4. Distribution - CHRISTMAS tree or FIR tree pattern- long axis of lesions along skin tension lines running parallel to ribs 5. Spontaneous resolution in 3-6weeks Treatment: Reassurance, self liming disease Symptomatic rx- calamine emollients, antihistamines, topical steroids Erythromycin , acyclovir,NBUVB can be given at acute stages