I beleive that GSH is the best thing we have done in caring for our son with cf. I contribute his good health mostly to the GSH. I was just telling my mom this morning (he has been on it for about 2 years) how thankful I am that the Lord led us to GSH. If we miss a day of GSH I can tell that my son starts clearing his throat alot and I can just tell how much it really does help him. We use the inhaled GSH twice a day. I would highly recommend anyone considering GSH to give it a try....you will be glad you did.