Mestinon

Mestinon (Pyridostigmine) is an acetylcholinesterase inhibitor used to treat myasthenia gravis and Sjögren's syndrome. It inhibits the acetylcholinesterase enzyme from breaking down acetylcholine, resulting in higher circulating levels of the neurotransmitter. It cannot cross the blood brain barrier, and so only works on the peripheral nervous system.

Mestinon and ME/CFS
Anecdotal patient reports of Mestinon are mixed.

A work in progress study of exercise intolerance in preload failure found that Mestinon improved exercise tolerance, but the study has not yet been published.

Mestinon and Gulf War Illness
Pyridostigmine was the medication given to Gulf War troops to protect them from nerve gas. But the nerve gas and pyridostigmine interacted causing brain damage to 25% to the 700,000 US troops. It is noted as being involved in two of the three syndromes experienced by troops suffering from Gulf War Illness as it also interacted with DEET. 250,000 US Gulf War troops suffer from persistent unexplained symptoms.

Interviews

 * 2018, Advancements in ME/CFS Research, David M. Systrom, MD; Brigham and Women's Hospital | ME/CFSAlert 98 (David Systrom, confirming some positive clinical results and plans for a clinical trial)

Learn more

 * Wikipedia - Pyridostigmine
 * "Mestinon for ME", Living With Chronic Fatigue Syndrome blog post, September 13, 2017
 * "A Mestinon Miracle: Vagus Nerve Stimulating Drug Helps Long Time ME/CFS Patient Exercise", Health Rising Blog, June 17, 2016