Sorry to read about your difficulty. From my experience cramping of the legs and feet are related to the pH of the body, which is related to diet.
Get yourself something called Tri-Salts. It is made up of three essential micro minerals: calcium, magnesium and potassium and carbonates and bicarbonates without sodium. It can be mixed with vitamin C crystals and the pH adjusted to individual needs. One teaspoon in a 16 oz glass of water makes an alkaline drink. After 15 minutes watch the cramping of the feet and legs dissolve away. The intestinal tract is also noticed to relax. Stools will loosen. Constipation goes.
If you find this works, then simply take notice of what food items that you normally ingest are considered alkaline and which ones are acid. And adjust your diet accordingly. And then you won't have to depend on the Tri-Salts product but only on what you put in your stomach.
I do not have any affiliation to this product.
Best regards, tuirya -*-