Emla cream contains two ingredients called lidocaine and prilocaine these belong to a group of medicines called local anaesthetics emla cream works by numbing the surface of the skin for a short time it is put on the skin before certain medical procedures this helps to stop pain on the skin however you may still have the feelings of pressure and touchadults it can be used to numb the skin before having a needle put in for example if you are having an injection or a blood test mino