saltsodium especially from a nonplant source does tend to raise blood pressure which can be helpful for some along with other properties or in the case of most harmful. It does not matter if it is Sea Salt with 88 tiny amts of additional trace minerals or not. Salt is salt, better always to obtain sodium from our food, rather than think we can shake a few sprinkles or swallow a concoction and work our way back to health. I have done all the salt therapies and drinking it adding it to diet and for my specific body type it is no good. I get all the sodium I need (actually a bit much) naturally from my diet.
However these forms of flush I do recommend as they are usually an isotonic solution which attempts to match the salinity of the body so that none is absorbed and the salt passes through. This works fine for some people and some people retain usually due to incorrect dosing misinformation or not drinking the solution fast enough.
For those who retain it, they may need to try a slightly hypertonic solution, just slightly above the recommended dosage, this because their bodies salinity may be already above average do to overuse or other faulty mechanism. By this I do not mean tablespoons more just perhaps 1/4 -1/2 tablespoon more.
It is important to use as natural a salt as possible like Sea Salt as some of the information circulating out there and even on these forum is grossly wrong. I saw someone here once who was given the advice or perhaps misunderstood it and was trying to consume over 2 gallons of heavily over salted water.