I believe it's been a couple of years now, but I had detox (or dehydration) so bad that I had to do four salt pushes in a row to get 100% relief.
It was very well worth it, as I had a horrible headache at the time! I had a 1/2tsp of RealSalt with 4oz warm water, and chased it with another 16oz of room-temperature non-salted water.
30 minutes later I did that a 2nd time.
30 minutes later I did that a 3rd time.
30 minutes later I did that a 4th time.
The fourth time was the charm.
(And yes, I literally could feel the pain leaving my body along with the eliminations that ensued from all that water and salt!)
Pain was alleviated 100%.
Most of the time AFTER that, I only had to do the salt push once or twice to get rid of an uncomfortable period of detox, which could have been anything from frontal lobe headache, to a feeling-I-needed-a-chiropractor, to simple fatigue.