I myself, Ryansm and others have discussed potassium intake for BP issues.
I have been researching potassium dosage and intake. It seems that although a sudden dose of 14 G of potassium may be enough to kill some smaller people who have been accustomed to very low intake for a long time, there is almost no limit to how much of it one might be able to ingest safely. Magnesium intake should also be very good, otherwise the potassium can't be used.
Here's something : http://www.mindfully.org/Water/2004/...ake11feb04.htm