Effect of avicatonin (chicken carbocalcitonin) on galvanic skin response: A randomized, prospective, double-blind, controlled study for are objectiveassessment of pain

In an attempt to objectively evaluate the analgesic effect of avicatonin (c hicken carbocalcitonin), galvanic skin response (GSR) was recorded in 18 pa tients with osteoporosis or osteopenia and backache in a randomized, prospe ctive, 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 o r inactive placebo was intramuscularly injected once a week for 4 consecuti ve weeks. In the avicatonin group but not in the placebo group, the area un der the curve (AUC) of GSR tracing was decreased, giving a significant diff erence 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.