Hi

I'm concerned about a friend she has an over active thyroid and has been on meds for quite a few years, but lately I've noticed that every so often her face will shake, I can't really explain it, except her face becomes distorted. It only lasts for seconds and each time I thought I had imagined it. I mentioned it to her the first time it happened and she got annoyed and said it was me imagining it. Any ideas what this can be or do I need to see the Optician?