Tracy,

I wasn't sure if you saw what I wrote regarding your adverse response to IVIG, so I am copying it again here.

Tracy,

I was suspecting you are on Gammunex. Gammunex has a very high concentration of glycine (and so does liquid Gammaguard). Glycine is a calcium chelator. this means that it leads to minor changes in the level of calcium in your blood. such changes will not have any effect on normal, healthy people, or even most patients with neuromuscular disease, but some MG patients are extremely sensitive to those minor changes in calcium.

most neurologists are totally unaware of this problem, even though it was described in the medical literature. and I believe that 99/100 neurologists will attribute shortness of breath to "anxiety", so obviously will not report this "unimportant" side effect. (that is why it is very hard to tell what the true extent of this problem is).

the bottom line is that you may want to try and switch to an IVIG preparation that does not have glycine in it. although, all IVIGs contain additives that decrease the pH, so may have an adverse effect.

If this is the cause of worsening in your symptoms then you should also be cautious with plasmapheresis, which will have a similar effect on calcium level shifts.

MG is not one disease, so it is also important to know if you are AchR pos. MuSK pos. or seronegative and what were the results of your SFEMG (if you had that done), as this may be important in the way you respond to treatment. for instance-some patients with MuSK will not respond well to mestinon. patients with MuSK are probably more prone to steroid myopathy and respond less well to steroids etc.