那塊棉花含有 EMLA , 低熔點局部麻醉劑混合物
http://en.wikipedia.org/wiki/Lidocaine/prilocaine
A 5% emulsion preparation, containing 2.5% each of lidocaine/prilocaine, is marketed by AstraZeneca under the trade name EMLA (an abbreviation for Eutectic Mixture of Local Anesthetic).
5% EMLA 乳液含有 2.5% 利度卡因(lidocaine) 與 2.5% 普魯卡因 (prilocaine).