Is it normal to get charle horses in your jaw is this a med related thing?!?
Stress can make the muscles in you jaw tense. Connected to anxiety, fm, and other issues. Try things to teduce stress. Also try heat and massage on muscles of the jaw, neck, and upper chest, just below collar bones. Gentle stretches of neck in all directions.
I get it where I have to open my mouth wide to relax my jaw. I hope this helps.
Fibro can also give you lock jaw -