I am no longer bothered by leg cramps at night - I found the cure!
Before I was diagnosed with multiple myeloma, I had a SERIOUS CASE of plantar fasciitis that really crippled me. I found these boots worn at night that keep your feet in dorsiflexion (toes toward head) on the internet. From the first night, they helped and my plantar fasciitis resolved in about 3 months time. I stored the boots away in the closet wondering if I should get rid of them.
Well, my leg cramps from my myeloma treatments are a thousand times worse than plantar fasciitis EVER WAS. When they occur, mostly at night while I am in bed, the only cure is to bring your toes toward your head, best accomplished by getting up and walking around - YELPING LOUDLY. So, I remembered the boots for some reason.
I put the boots on at night 3 days ago and I have NOT had a single leg cramp since! Getting used to the boots at night isn't that hard. Unlike when I used the boots for plantar fasciitis, I have made them very loose and can easily slip in and out of them which makes going to the bathroom easy as you cannot walk in the boots.