One of the causes for your mother's symptoms could be peripheral neuritis
She can take neurotropic drugs like Neurobion
forte once daily for 6 weeks minimum. This is available over the counter and helps in relieving the itching and burning sensation.
is also found to be very effective in these conditions. Please get her blood sugar levels tested, as Diabetes
is one of the common causes of peripheral Neuritis. If, she is a known diabetic, keep her blood sugars under normal control.
Hope this helps.