PROBLEM TO BE SOLVED: To provide a pain evaluation method of liquid medicine administration and a selection method of liquid medicine administration.SOLUTION: The pain evaluation method of liquid medicine administration is configured to: prepare a rat 12； anesthetize the rat 12 by inhalation anesthesia； dispose a measurement electrode 24 on a semitendinosus muscle 12b of the rat 12 which is subjected to anesthetizing； measure a myoelectric potential of the semitendinosus muscle 12b by the measurement electrode 24, while stabbing a syringe needle 18 to a subcutaneous of sole 12a of the rat 12 which is subjected to anesthetizing； after the myoelectric reaction by stabbing the syringe needle 18 is disappeared, administer a liquid medicine to the rat 12 which is subjected to anesthetizing, via the syringe needle 18； then perform at least one of measurement of a duration time T of the myoelectric reaction caused by administration of the liquid medicine, and measurement of EMG intensity obtained by integration of an absolute value of the myoelectric potential since occurrence of the myoelectric reaction by administration of the liquid medicine, until the reaction is disappeared.SELECTED DRAWING: Figure 2【課題】薬液投与による痛みの評価方法及び薬液投与の選定方法を提供する。【解決手段】薬液投与による痛みの評価方法では、ラット１２を準備し、ラット１２を吸入麻酔にて麻酔し、麻酔されたラット１２の半腱様筋１２ｂに測定電極２４を留置し、半腱様筋１２ｂの筋電位を測定電極２４で測定しながら、麻酔されたラット１２の足底皮下１２ａに注射針１８を穿刺し、注射針１８の穿刺による筋電反応が消えた後に、麻酔されたラット１２に注射針１８を介して薬液を投与し、薬液の投与による筋電反応の持続時間Ｔの測定、及び薬液の投与による筋電反応が生じてから消えるまでの筋電位の絶対値を積分したＥＭＧ強度の測定の少なくとも一方を行う。【選択図】図２
