Effect of Avicatonin (Chicken Carbocalcitonin) on Galvanic Skin Response: A Randomized, Prospective, Double-Blind, Controlled Study for an Objective Assessment of Pain

. In an attempt to objectively evaluate the analgesic effect of avicatonin (chicken carbocalcitonin), galvanic skin response (GSR) was recorded in 18 patients with osteoporosis or osteopenia and backache in a randomized, prospective, double-blind, controlled study. Backache on examination and in daily living was assessed weekly by scores utilizing a questionnaire. After two measurements 1 week apart on induction of backache with a maximum anterior flexion of the back from a supine position, either 20 units of avicatonin or inactive placebo was intramuscularly injected once a week for 4 consecutive weeks. In the avicatonin group but not in the placebo group, the area under the curve (AUC) of GSR tracing was decreased, giving a significant difference between the avicatonin and placebo groups after the second week. The pain score obtained by questionnaire decreased in both groups, suggesting a placebo effect. Galvanic skin response may provide a breakthrough to the objective and reliable evaluation of the biological response to pain which could not be accomplished by questionnaires based on subjective impression markedly influenced by emotional and psychological factors.