Mestinon fixed my muscle weakness and PEM

I had my first major breakthrough with long hauling this week. I want to note upfront, this probably won't help the majority of people here. But I'd guess there is a significant number of people who don't realize they have myasthenia gravis -- a relatively rare autoimmune disorder.

I have a very cooperative doctor who was willing to trial mestinon (aka Pyridostigmine) because I've heard it's being used off-label for long covid. Most people use it for POTS. But to my surprise, my muscle weakness disappeared. I did a test run off mestinon and found that all of the weakness returned.

My neurologist did a blood test and an EMG for myasthenia gravis. They were both negative. But my response to mestinon is indicative of the disease. Some neurologists will diagnose you with myasthenia gravis based on responsiveness to mestinon alone. Around 20% of people will test negative on bloodwork, despite having the disorder.

For a very long time, I thought my PEM was CFS. I couldn't walk more than 5 minutes without experiencing a flare up. But now it appears it may be due to myasthenia gravis (which was probably triggered by COVID). I don't have any of the typical eye/breathing/throat issues associated with the disease. And yet, the mestinon works.

Myasthenia gravis is known as the snowflake disease because everyone has a unique presentation. I'm sure a lot of long haulers here can relate.

Sleep apnea is also highly prevalent in myasthenia gravis, which may explain why I acquired it after COVID. And why my fatigue greatly improved after getting on CPAP.

I am feeling more hopeful than I have in my entire 2-year journey with this disease. It's a serious diagnosis (which I'm still working toward), but the mechanism of action is well understood and there are multiple treatments. Including many more in the pipeline over the next few years.

tl;dr Mestinon fixed my muscle weakness, as a result I may have a treatable autoimmune condition known as myasthenia gravis.