"An unpleasant abnormal sensation, whether spontaneous or evoked. Note: Compare with pain and with paresthesia. Special cases of dysesthesia include hyperalgesia and allodynia.
A dysesthesia should always be unpleasant and a paresthesia should not be unpleasant, although it is recognized that the borderline may present some difficulties when it comes to deciding as to whether a sensation is pleasant or unpleasant. It should always be specified whether the sensations are spontaneous or evoked."