Pruritus, Or The Symptom Of Itching , is due to disturbance of function of the sensory nerves, and may occur quite apart from any co-existent eruption which involves these nerves. The conditions determining the pruritus may be innate or acquired in the nervous system, and in certain persons whose sensory nerves are, so to speak, on edge all sorts of slight influences may excite itching, such as undressing, the warmth of bed, a bath, cold, etc. Then the symptom may be excited reflexly as exemplified in the nasal and anal itching due to thread worms in the lower bowel. The sensory nerves again may be disturbed by the circulation in the tissue of noxious products elaborated in the system, as in diabetes and jaundice, or accumulated by faulty elimination. Sometimes people have an idiosyncrasy against certain articles of diet, and tea and coffee are not infrequently incriminated. In the common senile pruritus it is often difficult to estimate the relative potency of such factors as atrophic skin changes, metabolic disorders, and inefficient elimination. Obviously where the diet or digestive organs are in any way at fault or the elimination of waste products imperfect, we must meet the difficulties by an appropriate diet. In some intractable cases it is advisable to try for a period some special diet, such as the milk, or lacto-vege-tarian, or Salisbury cure.