What do people do to stop nighttime leg cramps?

This is going to sound completely ridiculous but please bear with me. I get terrible leg cramps at night in bed and I do this, and it works.
Put a bar of deodorant soap under the fitted sheet where her legs rest in bed. When she feels a leg crap coming on, rub on it and that will stop it. Also keeping a stick of anti-perspirant deodorant by the bed and rubbing on when the cramp starts will stop it. Or swiping some of the deodorant on the legs before bed will stop leg cramps from starting up. If not totally stop them, they reduce the severity.
The deordorant has to be a stick. Not a spray. Not a roll-on. Not an all-natural one either. A regular anti-perspirant deodorant stick. Try it. This works

Does she have a favorite pair of supportive shoes?

When I get leg cramps I put on a pair of Birkenstock sandals and get back into bed.

For me, this works every single time without fail.

Ask her doctor first, but plain tonic water which contains quinine, (check the label), such as Q-Tonic or Fever Tree work instantly for my husband when he gets nocturnal leg cramps. There is a minimal amount of quinine in the product but it does seem to work.

Bananas!

Hi, I know this is a late response, but have you found help for your mother’s leg cramps? I see she was going to start taking magnesium, that’s good. My mom has this issue as well and I gave her a product called Calm. It is primarily magnesium, but it is a powder you mix with water and drink. It really does help to “calm” nerves and anxiety too. I have used it myself as needed.
Of course, you should ask your mother’s doctor before giving it to her, especially since she is already taking magnesium.
It is available at natural foods stores. It is a little tart; I sometimes add stevia. I hope your mom has found some relief.

This is definitely a question for Mom's MD. Leg cramping has MANY reasons, anything from medications to lack of needed electrolytes as a side effect of medications to a myriad of other causes. Have an appointment made for Mom this week.

I used the apple cider vinegar when I was undergoing chemo and had awful leg cramps at night. It tastes awful, but it worked!

Another option is Gabapentin, has she tried that?

My DH wears compression hose every day, all day. This has greatly reduced his 'jimmy legs' or the creept crawly sensation he'd get.

I think it's a trial and error kind of thing. So annoying!

I don't know if this will help your mom, but I too occasionally get what I call "Charlie Horses" in my legs and feet at night. Sometimes I can walk them out, but usually I just get up and take a couple large tablespoons of apple cider vinegar(I use the kind with the mother)and almost instantly they will stop.
Wishing you and your mom a good solution that will work for her.

Here's a helpful article from the Mayo Clinic:

https://www.mayoclinic.org/symptoms/night-leg-cramps/basics/when-to-see-doctor/sym-20050813

Summary:

"Most of the time, no apparent cause for night leg cramps can be identified. In general, night leg cramps are likely to be related to muscle fatigue and nerve problems. The risk of having night leg cramps increases with age."

Known causes are:

Structural disorders like:
- Peripheral artery disease (PAD)
- Spinal stenosis

Metabolic problems:
- Acute kidney failure
- Addison's disease (adrenal insufficiency)
- Anemia
- Chronic kidney disease
- Cirrhosis (scarring of the liver)
- Hyperthyroidism (overactive thyroid)
- Hypothyroidism (underactive thyroid)
- Type 1 diabetes
- Type 2 diabetes

Medications and procedures:
- Blood pressure drugs
- Cholesterol-lowering drugs (statins)
- Dialysis
- Diuretics (water retention relievers)
- Oral contraceptives

Other conditions:
- Dehydration
- Diarrhea
- Muscle fatigue
- Nerve damage, as from cancer treatments
- Osteoarthritis (disease causing the breakdown of joints)
- Parkinson's disease

Anyone had a PT suggest foot & ankle pump exercises - to increase lower leg circulation?
Just wondering if that would have any effect?

Unfortunately, painful nocturnal leg cramps are very common in the elderly and very little can be done to stop them. There is a vast amount of medicines and other measures that people try with none or limited results. In old people, the tendons become shorter and the muscles weak. Also, they exercise very little and remain in the same position for many hours. All of this contributes to having leg cramps at night. Rarely, they are the result of electrolyte imbalance, which is rare if you eat a normal diet. Giving electrolytes when they aren't needed can be dangerous. Potassium, Magnesium or other deficiencies must be proven by laboratory tests, not by guessing alone.

Try dill pickle juice, just an ounce a night will help if these are caused by electrolyte deficiency. It helps faster to correct the problem then anything we have used. Maybe a small bit by her bed until they are under control.

Do give her the magnesium as well, it will help that and other things and help her sleep well.

Yes, you tend to point your toes when you have a cramp but you go the opposite way.

Potassium helps to prevent cramps, like eating a banana.

If she gets a cramp while in bed, this is what my 93-yr old mom's PT told her to do;

Lay flat on your back. Keeping your cramped leg straight and your toes pointing up (ie like how your leg and foot are when you're standing upright on a floor) - then slowly raise that leg as high as you can from the hip without bending the leg and keeping the foot in that same position. It really works for my mom and I've had to do it myself and yes, it does relieve the cramp quickly.