This section is from the book "Materia Medica And Therapeutics Inorganic Substances", by Charles D. F. Phillips. Also available from Amazon: Materia medica and therapeutics.
When pruritus is dependent on discharge, or other source of irritation, possibly parasitic, injections and lotions containing "bisulphite of soda" (gr. xv. ad 3 j.) have been found serviceable (Lancet, ii., 1871, p. 454). The itching of lichen and of true prurigo senilis may also be relieved by lotions containing sulphites.