I posted this on an old POTS thread yesterday, but I thought I'd start it as new one today for more eyes to see. Would love thoughts! I know the healthrising and phoenixrising communities and researchers have examined acetylcholine before. I wanted to take the concept one step further in looking for biomarkers which would predict who would do badly on antivirals and first generation histamines, some antibiotics, anesthesia and other anticholinergic drugs. I've been reading government studies on POTS, ME, CFS, MS, Autoimmune Myasthenia Gravis, Rheumatoid Arthritis and Pseudocholinesterase Deficiency, all of which consider acetylcholine. A theory of Alzheimers is that it's caused by anticholinergic medication use throughout life. (Which lowers levels of acetylcholine in the body). Rituxamab targets acetylcholine receptors. Apparently abnormal growths in the body, including cancer, can trigger an autoimmune response. I guess this is why Rituxamab, though a cancer drug, was found to have application to other autoimmune diseases. There's a test which determines if a person would be sensitive to the anesthetic Succinylcholine. (It also tests for organophosphate poisoning.) Could this be the "biomarker" for patients who won't respond well to anticholinergenics? https://labtestsonline.org/understanding/analytes/cholinesterase/tab/test/ https://www.ncbi.nlm.nih.gov/pubmed/26785775 Effect of M3 muscarinic acetylcholine receptor deficiency on collagen antibody-induced arthritis. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3497293/ Relation between Pro-inflammatory Cytokines and Acetylcholine Levels in Relapsing-Remitting Multiple Sclerosis Patients (there's many more studies that examine MS and acetylcholine) https://www.ncbi.nlm.nih.gov/pubmed/25087056 The value of acetylcholine receptor antibody in children with postural tachycardia syndrome. https://www.ncbi.nlm.nih.gov/pubmed/26399744 Antibodies to β adrenergic and muscarinic cholinergic receptors in patients with Chronic Fatigue Syndrome. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3497293/ Relation between Pro-inflammatory Cytokines and Acetylcholine Levels in Relapsing-Remitting Multiple Sclerosis Patients https://www.ncbi.nlm.nih.gov/pmc/articles/PMC153771/ Immunization with neuronal nicotinic acetylcholine receptor induces neurological autoimmune disease https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5105265/ A targeted genome association study examining transient receptor potential ion channels, acetylcholine receptors, and adrenergic receptors in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis https://www.ncbi.nlm.nih.gov/pubmed/15190684 Alzheimer's disease and acetylcholine receptors. https://rarediseases.org/rare-diseases/pseudocholinesterase-deficiency/ https://www.ncbi.nlm.nih.gov/pubmed/1692155 Acetylcholine receptor antibodies in primary biliary cirrhosis: characterization of antigen and idiotypic specificity.