[bjpete]

you might want to contact DAN for the best medical advice for clearing your ears. There is always a risk of having a " reverse squeeze" this happens when the medications wear off and you experience pain upon ascent. If you are SCUBA diving you can always stop while coming up, but obviously in freediving this is difficult or impossible to do. Anyway with the reverse squeeze you will rupture your eardrum going to the surface which can result in vertigo/dizziness.
This just my 2 cents worth.

Brian