I have used an inhaler while breastfeeding and did not really see any difference in my child's behavior. I know others who have used it with no problems. This is only my personal experience. I have had frequent asmatic bronchitis and one bout with pnuemonia and I would certainly go ahead and use the inhaler! The discomfort of not breathing well can be very streddful and tireing. If you notice an extreme change in your child you can always stop taking the medication, but it's worth a try in my humble opinion. Diane Karnbach, LLL Leader Va Beach, VA