I was prescribed it for stone prevention. I found that It stopped type cramps of the Charlie horse like a magic potion.I mourn the end of the packets!! How do I get any? Do I need a prescription? ## From what I could gather, Neutra Phos is a powder formulation of sodium and potassium phosphate. It contains the equivalent elemental phosphorus 250 mg (8 mmol), sodium 164 mg (7.1 mEq), and potassium 278 mg (7.1 mEq) per packet. It is used for the treatment of phosphate deficiency and is often ordered by renal doctors for hemodialysis patients. You may be able to get your doctor to write another script for it if you let him or her know how it's been helping you in a number of other ways. Often times, these medications have wide application of off-label uses that are worth inquiring about.