Abstract: The invention relates to a measuring instrument for the measurement of an existing pain or a feeling of nausea of a patient. The measuring instrument induces pain in an arbitrary body part of said patient, by supplying an electrical current. The measuring instrument provides a current increase into said body part, until said induced pain is experienced by the patient as being as great as the existing pain/nausea. The current is supplied from a current source arranged in the measuring instrument via wires (H, I) and electrodes (C, D), said electrodes being applied onto that part of the body in which pain is to be induced. When the pain induced is experienced to be as great as the existing pain/nausea, the body part is removed from the electrodes, whereupon a pain value is registered and shown on a display (F).