Causes of generalized itching:

I) Skin diseases:

i. Urticaria
ii. Scabies
iii. Eczema
iv. Lichen planus

II) Parasitic infestation:

Onchocerciasis

III) Thyroid diseases:

i) Hyperthyroidism
ii) Hypothyroidism

IV) Liver disease:

i) Obstructive jaundice
ii) Liver failure

V) Hematologic disorders:

i) Hodgkin’s lymphoma
ii) Iron deficiency anaemia
iii) Polycythaemia rubra vera

VI) Renal disease:

Chronic kidney disease

VII) Viral infection:

HIV infection

VIII) Metabolic disease:

Diabetes Mellitus

IX) Drug induced:

i) Morphine
ii) Cocaine

X) Neoplasia:

Bronchogenic carcinoma.

Treatment of itching:

i) H1 receptor blocker
ii) H2 receptor blocker can also be added
iii) Corticosteroids- local, oral or injectable- according to the need
iv) Naltrexone- if due to morphine or cocaine
v) Topical use of methanol
vi) Treatment of the primary cause.