I use Hylands Leg Cramp. They sell it at Walmart. It works great and is quite inexpensive.

Hylands does seem to work
"According to available information, the best natural remedy for leg cramps associated with Parkinson's disease is magnesium supplementation, particularly in the form of Magnesium L-Threonate, as it can improve brain magnesium levels and help alleviate muscle cramping while potentially supporting cognitive function as well;.
Other natural approaches to manage leg cramps in Parkinson's include:
Regular stretching: Focusing on lower body stretches can help relax muscles and prevent cramps.
Massage therapy: A qualified massage therapist can help relieve muscle stiffness and pain associated with cramps.
Gentle exercise: Activities like yoga, tai chi, or walking can improve flexibility and muscle function.
Heat application: Applying heat with a heating pad or warm bath can soothe tight muscles.
Hydration: Staying properly hydrated can help prevent muscle contractions.
Important points to remember:
Consult your doctor:
Before trying any natural remedy, especially if taking medications, discuss it with your doctor to ensure it's safe and appropriate for your specific situation.
Dosage matters:
Follow recommended dosage guidelines for magnesium supplements to avoid potential side effects."

Pickle juice

I am a caregiver, but I did have bad leg cramps. My doctor told me to take COQ10, I take 100mg. This has really helped me.