Myasthenia Gravis Support Group
Myasthenia gravis (MG) is a neuromuscular disease leading to fluctuating muscle weakness and fatiguability. The hallmark of myasthenia gravis is muscle weakness that increases during periods of activity and improves after periods of rest. Although myasthenia gravis may affect any voluntary muscle, muscles that control eye and eyelid movement, facial expression, and...
http://www.ncbi.nlm.nih.gov/pubmed/2003276
Although we are told not to take Mestinon or pyridostigmine before the EMG's, nobody says anything about not having coffee or other caffeine before them. Since caffiene is an anticholynesterase as well, I wonder how many of our negative, borderline and suspicious findings that might otherwise be positive are due to caffeine ingestion before the test. There are other articles than the one above that discuss caffeine and it's role. Just put in caffeine and acetylcholine in your search engine.
I picked the role of caffiene up on another site, but got to thinking about whether it is strong enough to affect results, especially if right before an examination. I think I had an unusual cup of coffee before mine. I don't often drink it, but it is better than the tea you get traveling. Even decaffeinated coffee has some caffeine. b.
Although we are told not to take Mestinon or pyridostigmine before the EMG's, nobody says anything about not having coffee or other caffeine before them. Since caffiene is an anticholynesterase as well, I wonder how many of our negative, borderline and suspicious findings that might otherwise be positive are due to caffeine ingestion before the test. There are other articles than the one above that discuss caffeine and it's role. Just put in caffeine and acetylcholine in your search engine.
I picked the role of caffiene up on another site, but got to thinking about whether it is strong enough to affect results, especially if right before an examination. I think I had an unusual cup of coffee before mine. I don't often drink it, but it is better than the tea you get traveling. Even decaffeinated coffee has some caffeine. b.
I hope others can site incidences of this...Maybe it will help with testing.
I found it/am finding it very interesting how it helps MG now( same mechanism effect as mestinon), as I wasn't aware of it before until you told me, but I was suggesting to someone taking amphetamine here to take caffeine as a safer alternative. It was quite a debate actually, and the caffeine suggest wasn't taken serious enough because I perhaps did not perhaps present it correctly. Speaking of amphetamine, I am wondering if that acts in a similar way, but even more powerful, or?
Still studying...when I can.
As always thanks for sharing. Hopefully people will find this interesting.
If caffeine can effect test results (raises hand)... this may be a contributing factor to my confusing test results. I had an "Abnormal" EMG which suggested probable MG, but then a "Normal" SFEMG. A couple of days ago, at my appointment, my neuro told me he was very surprised and confused about these two results.
The excessive amount of caffeine I consumed that day (especially at lunch prior to the test) might explain it. I drank a lot that day, but I do remember all the restroom trips I took from the waiting room. Funny how we compensate and self medicate without even really thinking about it huh?
I had some caffeine before my EMG test as well, but not as much. I wonder if the the numbers would be "diagnostic" if I skipped the caffeine and more than just one dose of mestinon.
I am going to look into this more with you! Thank You!
The amount of caffeine I drink in a day is almost the amount of a regular cup of coffee...I have never liked coffee.
http://www.emedicinehealth.com/electromyogram_emg_and_nerve_conduction_studies-health/article_em.htm
I also wonder if the dosage should be considered. I am taking 120mg mestinon every four hours. Maybe that should be considered in the amount of time to be mestinon free as well.
Pat
Hugs,
sherry
~sherry
That's encouraging for those of us who are still struggling for a firm diagnosis and whose EMG studies are just borderline. It is only people who are seronegative who start posts with "yay, I have MG." Knowing you're not lazy or crazy, and the doctor believing it too is such a relief! b.
I am so glad your diagnosis struggle has ended and you can move forward with treatments for MG!
With more research and information, hopefully the caffeine free testing will help others get their diagnosis confirmed more quickly and save them the issues some of us have had.
I love that we can brainstorm ways to make a difference in the lives of others in addition to our own!
Love, Becca