I found this on the net where people were sharing information about CF.  Do not know how well it works for others.  This is more a survey than a recommendation.  My sense is that breathing into the nausea is quite valuable for some. Whether it is bad for CF victims I do not know but I wonder if they ever try as hard as this person did and get similar results. Use it at your own risk and always be careful. See my comments below the article. Mike

Here's an exercise for you to try. Sit on the floor, legs crossed, back straight, head slightly tip forward (so your looking at an angle of 60 degrees in front of you). Breathe only with your diaphragm, leave your chest relaxed so it can expand and contract by itself. The rate and force of your breathing should be full, hard and equal on both the in and out breath. Breath only through your nose if you can. Focus your concentration on the air flow at the end of your nose, this way you can tell if your breath is equal on the inhalation and exhalation. Do this exercise on an EMPTY stomach. With this exercise find a breathing rate which is good for you.

At first, you may not be able to sustain a fast hard breath without puking all over the place. Find a level at which you can go for 15 minutes. After a month of doing this, you will see a dramatic increase in your capacity. I usually do this 10 minutes after my Polmozyme inhalation.

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Warning - If you feel light headed, nausea, headache... You are doing the exercise too hard. Back off the intensity of the breathing to what is comfortable to you but is still productive. The key to this exercise is to be able to listen to your body. Remember heed the warning on doing this on an empty stomach or you will more than likely end up with a techno-color room. 

Fifteen minutes may be a little much for first starting off, start with 5 minutes then work yourself up to 15 as your endurance and strength improves.

Let us know how this works for you.

Did you notice any improvements?
Was the exercise too demanding?
Was it effective?
Any comments at all?
If you did not continue it, will you be able to share as to why?

From Mike:

The nausea parallels feedback from breathing work and cathartic breathwork in that the body seems to have a way of resisting progress or rapid increases in energy by creating nausea.  We have found that to just let the nausea occur and if we need to vomit then do so. The actual incidences of vomiting are, in my experiences with breath work and breathing work, less than 2%.  So I have to assume that it is in most cases more a energetic defense mechanism and less of a " symptom" of something truly negative and life threatening. 

Are there cross-over similarities with CF? I have to think so. But I leave that up to you to discover and confirm. Please report back to me at cysticfibrosis@breathing.com This could be a major insight. People with CF need your help.

Patients with cystic fibrosis (CF) are at risk of developing Vitamin K deficiency because of pancreatic insufficiency, hepatobiliary disease, or both.  Vitamin K deficiency is common in un-supplemented patients with CF and pancreatic insufficiency and routine supplementation should be considered in all of these patients.

See also PROEFA.

Highly recommend the liver cleanse.