The present invention provides a portable handheld static-electricity generator and a method thereof for alleviating pain in at least one portion of patient's body, comprising: a movable brush, a polymer assembly comprising a rubbing-surface portion upon which the brush rubs and an automatically-operated mechanical unit. The polymer assembly having affinity to a defined charge such that when the movable brush rubs the rubbing-surface of the polymer assembly for a predefined time a static electricity is generated.