By:Dr Neda adibi Researcher and dermatologist in IUMS

 The pruritus is an unpleasant sensation which may lead to scratch  The most common complaint in dermatology  With or without skin lesion  Can be a manifestation of systemic disease(10-50%) 

 Systemic etiology like:  Metabolic disorder,hematologic disease,malignancy,HIV,complication of pharmacologic agents,neuropsychiatry disease

1. Psoriasis <85% 2. ESRD 60-80% 3. CTCL 70-80% 4. Hodgkin 10-30% 5. Pregnanacy 20% 6. Herpes zooster 60%

 Localized or generalized lesion is not predictive or systemic disease  Acute onset,without skin lesion less likely to be systemic  Butterfly sign:sparing of the upper mid back may rule out skin problems (it may be psychogenic or systemic)

 Most non dermatologic pruritic patients show only excoriation but not primary lesion  Urticaria and mastocytosis have rubbing and pressing not scratching  Involvement of several family members may be due to scabies  Exacerbation after bath may be due to polycytemia or aquagenic pruritus

 Nocturnal generalized pruritus,chill and fever may detect hodgkin (pruritus may be up to 5 year before lymphoma)  Most pruritus interferes with sleep except psychogenic

 Carefull examination of nail,scalp,hair and lymph node,liver and spleen  No geneneral need for LAB  Generalized pruritus of unknown etiology  ESR,CBCdiff,LFT,FBS,TFT,fe and ferritin  Stool for parasite  CXR

 Scabies:local or general with a burning component,starts 3-6 week after first infestation  Pediculosis  Atopic disease :attacks- heat,perspiration,wool,stress,contact with air may provoke  Summer type and winter type

 Patients with psoriasis y for rarely respond to antihistamines  Prurigo nodularis:more in middle aged women  Atopy,psychological stress, may be underlying  Most effective treatment is thalidomide  200 mg/d for at least 6 months

It is independent of water temperature or its salinity It starts 30 minute following water contact and lasts for 2 hours Begin in lower extremity and then generalized with sparing of head,palm,sole and mucosa Treatment cimetidine,colestiramin cyproheptadin,PUVA,UVB,topical capcaiecin two times per week for 4 week

 Folliculitis and impetigo may cause pruritus  HSV,varicella,HIV and viral exanthems

 DM,hepatic dysfunction,renal dysfunction and tyroid problem  Polypharmacy  Lice and scabies  Most common cause is xerosis

 Decrease the frequency of cold and hot bath and alkaline soap  Decrease the frequency of bath  Moisturizers  Post CVA using amitriptelyne and carbamazepin

 1-5 % of people more in men  % are primary  Cause:dietary like excessive coffee intake,poor heigiene,psychogenic  Rule out of anxiety and depression,patch test,colonoscopy in refractive cases  pinworm in children

 Treat with cool compress,sitz bath,fragrance free soap,mild corticosteroid cream  Topical capcaiecin

 Acute:infection and ACD and ICD  Chronic:dermatosis like psoriasis,LSA,malignancy 

 Scalp folliculitis seborhoeic dermatitis,psoriasis and folliculitis  Wound healing may cause pruritus  Post burn pruritus  Renal failure:gabapentine,ranal transplant  Hepatic diseas

 Myelodysplasia  Iron defficiency  Polycythemia  Lymphoma and lukemia

 Thyroid disease  Diabetes:genital and perianal pruritus is common in women with uncontrolled diabetes  HIV

 Drug related:estrogen,captopril,co amoxiclav,phenytoin,beta blockers,retinoid.,lithium

 Topical like corticosteroid,menthol,coal tar and anasthetics,urea.  Topical doxepin  Capcaiecin  Tacrolimus and pimecrolimus  PUVA and UVB