Help parents understand the importance of preventive asthma treatment by relating it to birth control: "If you have friends who are on their honeymoon but want to wait two or three years before starting a family, does the woman take a birth control pill only on the days she needs it?" (At this point, you have the parent's attention). "NO, because it won't work if she takes the pill only on those days. It's the same with medication to prevent asthma. It will NOT work if your child uses it only when he (she) thinks he needs it." Carl E. Smith, MD Harlan, Ky.