What should i do if there is someone who is being attack by asthma without an inhaler?

Call for help early: During asthma attack healthy people often increase their breathing rate to keep up with oxygen and breathing demands. This can only go on for so long until people get tired ("respiratory fatigue"), so i would say get them to help and assist them. Have them sit down, lean forward to breath and support them. Call for emergency health. Keep them away from smoke and heavy perfumes.