Some GERD meds cause nutrient depletion. I found this list:
beta-carotene, B1, B12, Folic acid, Zinc and Calcium.
Low calcium is notorious for causing leg cramps and restless leg.
Folic acid is essential for fetal development.
If you still have a terminal ileum, you can increase the B12 foods. If not, sublingual supplements or B12 shots will work.
Use your favorite search engine to find "drug-induced nutrient depletion" and you will find info about any other medication you are taking, and the source of the information.
My son was born with a faulty valve between his stomach and esophagus, so he must adhere to the strict diet and lifestyle restrictions. His leg cramps disappeared after he began to eat plain yogurt every day. If you choose oral supplements, it would be wise to consult your doctor first to assure you locate an absorbable form.